Is this very popular in Poland then? Being such a conservative country on the whole, I wouldn't have thought it would be.
Yes, very much so, and has been for many years. There are quite a few very well used official and semi-official naturist beaches in Poland. Usually very civilised places.
I suppose dog would be barred in case he is frightened by all the swinging parts and decides it's all a part of some biting game.
I only took mine once. He found a particular part of some sunbathing ladies just that bit too interesting for his wet nose and slobbery tongue.
Some people are very repressed indeed. Naturism's still popular though. If someone is so screwed up in the head that it upsets them, they can just go to the 95% of beaches where people wear bathing costumes instead.