I think this was common at YMCA's years ago.
When I was a freshman in college PE was a requirement. The gym was under construction so they had us take our PE at the nearby Y. We had swimming one quarter and you had to be naked. So picture 30 fit young guys milling about the pool area starkers. It was pretty hot and I had to do my darndest to keep things under control if you know what I mean.
Loved the experience actually. Once, me and one other guy were the only ones able to swim the length of the pool underwater up and back without coming up for air. We both got slapped on the bare ass from the other dudes after doing that. Ask me how many times I've relived that moment in my mind!
Only creepy thing was this Y was managed by these out of shape old guys who used to watch us from behind a window in their office that faced the pool. I'm sure they loved their jobs.
This Y was in Jersey too.