One possible motto for the nudist lifestyle is "normal, just naked" - the idea being that there is nothing "special" about nudism beyond the mundane fact of being without clothing. Which means, that when nudists get together, they are not so much "doing nudism" as they are doing what any normal clothed person does, except that they happen to be doing it naked - and that's what makes it nudism. The fact that they're naked doesn't mean that it's some kind of perverted sex orgy or something.
Now, there is some value in this view, but it is ultimately flawed because if naked was truly normal, then there would be little reason to prefer nudity over being clothed in any given situation, essentially marking the nudists - those who insist on being naked - as having some kind of odd, and perhaps unhealthy, fixation.
The truth is, there are great benefits to being naked - both the physical benefits of not being restricted by clothing, and also the psychological benefits that come largely through the sensation of being unclothed in space, free and unhindered, and released from the bondage of mainstream society. There are practical reasons for preferring either nudity or clothing for specific tasks - clothing keeps one warm while walking in freezing temperatures, yet is effectively useless when going swimming. However, all things being equal - and sometimes even when the deck is stacked - nudists by and large prefer to go nude whenever they can get away with it. And this is mainly because of the physical and psychological benefits nudity has, that are sometimes (to some people) worth sacrificing the practicality of wearing clothing for (e.g., you might have a little bit more protection wearing a layer of clothing while playing volleyball, but the risk of minor injury is not so great as to outweigh the simple pleasure of playing the game nude and unencumbered).
The one area where nudism is frequently stated to be not normal is in the realm of sexuality. And this is largely a forced designation. Nudism is no more sexually pure than anything you might do clothed. However, nudism is often misconstrued as being a sexual lifestyle. This is inaccurate, and this unfortunate designation hurts nudism, because sexual lifestyles are unfortunately shamed and regulated in ways that no other type of lifestyles are. Nudists can't afford to let themselves be seen as a sexual lifestyle. It would destroy nudism. The most obvious example of this is that kids would no longer be allowed to be part of the nudist lifestyle, and nudism would not then be family friendly, which is one of its primary virtues. Viewed as a sexual lifestyle, nudism would be little more than any of the other marginalized sexual lifestyles, and not only that, it would be forcibly changed to fit the guidelines of a sexual lifestyle to the point where it would no longer resemble nudism anymore.
So to avoid this, nudists go far out of their way to disassociate themselves with the sexual lifestyles. Which is a defensible reaction. But I don't speak from the public mindset, I speak from a more evolved position. I understand nudism intimately, and I'm sophisticated enough to understand the difference between nudism and sexuality without having to keep them in opposite hands at all times. I'm looking forward into the future, the way the nudist lifestyle should be lived in an ideal sex-positive world, not in today's twisted sex-negative society.
And in this ideal world, nudism's approach towards sex would be the same as its approach toward everything else - normal. And this is the approach that I personally hold, though I may choose to modify the way I represent my views based on practical concerns about how this (broken) world currently runs. But in my head, in my ideal world, I don't see a problem with engaging in sexual lifestyles concurrently with my nudism. Because I'm smart enough to understand that the presence of sex during nudism doesn't make all nudism about sex. This is how I can consider myself to be both a nudist and an exhibitionist. It's because, though I enjoy exhibitionism, not every time I get nude is for reasons of getting an exhibitionist thrill. It's just like how, a nudist might get nude, but not always for nudism. If a nudist takes off his clothes to have sex with his girlfriend, he's not engaging in nudism, even though he's nude. The fact that I have an interest in exhibitionism doesn't mean that every time I'm naked in front of people it's because I'm trying to get a sexual thrill out of it.
Why do nudists get naked? Because it's relaxing. Because it's more comfortable than wearing clothes. Because it's cooler when the temperature's warm. Why do exhibitionists or sex freaks in general get naked? Because it's arousing. Because when they're naked they feel exposed, and they think about sex. Why do I get naked? For the first reasons or the second? The answer is, both, at different times (and sometimes, yes, even at the same time). Let me give you a live example:
I've been sitting here at my computer for the past few hours. I'm not wearing a stitch of clothing, and I haven't since I sat down hours ago. I took my clothes off before I sat down after coming from dinner. I was only wearing clothes during dinner because that's what is socially acceptable - I would have preferred to have been nude. But why did I take my clothes off? Was it for sexual reasons, or nudist reasons? It was for nudist reasons. I just wanted to be comfortable, and I took them off because I spend most of my time in my room naked. Because it's comfortable, and because I am a nudist.
Now, during the course of the few hours I've been sitting at my computer, let's say that at one point I get distracted and start looking at some porn (unintentionally, I swear :p). Naturally, I am aroused. Suddenly, I become conscious of my naked condition not simply as being free from the restriction of clothes, but also as being exposed, and this turns me on. At this point, I am not acting as a nudist, I am acting in a sexual manner. Eventually, I finish looking at porn, and I go back to doing whatever other nonsexual things I was doing at the computer. My arousal subsides, and my thoughts of sex vanish. I am once again a nudist, sitting at my computer naked because it's more comfortable that way.
Does my session of looking at porn change the whole period of sitting at my computer from being a nudist activity to a sexual activity? No. I was engaged in sexual activity while I was looking at porn, yet I was engaged in nudist activity during the other periods when I was not doing anything sexual in nature. The mere presence of that sexual activity does not change the nature of the rest of my nudist activity, nor does it change my justification for being naked during my nudist activity. The reason I was nude during my nudist activity is not because I intended to engage in sexual activity and was getting prepared for it. I was naked for purely nudist reasons.
In fact, in a similar case, my state of undress may be unrelated to my sexual activity. Were I clothed during the whole period of sitting at my computer, then during the period where I looked at porn, I might not have the urge to take off my clothes for sexual reasons. I might enjoy myself sexually without taking my clothes off. In yet another case, closer in detail to the first, I might have been naked during the sexual activity, but I might not have been conscious of my nudity as a sexual thing during that period. In that case, I may be engaged in sexual activity, yet the reason for my nudity would be the same nonsexual, nudist reasons that I had for being nude during the period when I was engaged in nonsexual activities. Indeed, in that case, I would be simultaneously engaged in a nudist activity and a sexual activity.
Nudists don't want you to know this, but it's possible to have sex while engaging in nudism. The point that too many people pass up, though, is the fact that even if one does have sex while engaging in nudism, this does not indicate that nudism itself is a sexual activity, anymore than being clothed is a sexual activity because you happened to watch porn once while you were fully dressed.
Unfortunately, the way the world is, nudists have to be extra careful to unnaturally extricate their sexual urges and activities from nudism, for the sake of their image. For a person like me, who believes that life is by and large a sensual - and in some sense, sexual - experience, it can be frustrating to have to pay lip service to this asexual model. Know that I am willing to do so, because I understand the reasons for it - and more importantly, the repercussions for not doing it - but understand that my enlightened views are what allow me to be a highly sexual creature otherwise while not, in my mind, compromising my own personal dedication to nudism.
P.S. You might think the fact that I (and others) bring the topics of sex and nudism together frequently reveals that there is some kind of connection between them. The reason I bring them up often is because I am both a nudist, and I am interested in sex. So I enjoy talking about them. But the reason the two often get talked about together is precisely because they are frequently mistaken to be connected. People love to talk about sex, and to many people, groups of naked people make them think about sex. So there you have the "connection". Tons of people speculating that nudism is sexual, and tons of nudists proclaiming just the opposite. As soon as we all grow up and stop making such a big fuss about whether or not nudism has anything to do with sexuality, then I'll no longer have a reason to talk about them in the same breath, either. I'm telling you right now, it shouldn't be that important. (But until we get a grip on our collective social sexual dysfunction, I fear that it will be).