When I was in my late 20s I used to drive up to a nude beach occasionally and spend the day there, getting an all-over suntan. After a while it got a little monotonous; everything there was flesh tones.
I would come away with my libido charged up a bit, even if I wasn't consciously people-watching. So maybe nudists get a little extra energy from that.
I would have no problem doing a weekend at a nudist camp in the company of people my own age. But my wife has absolutely ruled out anything involving public nudity, so that's not going to happen anytime soon.