I don't understand what you imagine to happen in saunas. They are places where you relax yourself or with a couple of friends, you're not there as a showpiece for others nor do you ogle at the fellow saunagoers.

Edit: I saw your other comments, we have no common ground so let's not continue this discussion.

Well, first of all, nothing disgusting about swingers clubs; wouldn’t be my cup of tea personally, but provided they’re consenting adults there’s nothing wrong with it.

But also, like, mixed saunas, generally, aren’t sexual at all. The mere presence of naked people does not imply sex.