It's a bathroom, if it's in the men's bathroom, which means, no women...then I see nothing wrong. Of course, there are going to be women that come in to use the bathroom, if the women's is crowded, by they do that on their own merit.
Like, lewd, crude things in men's bathrooms don't exist. From drawings, phone numbers to porn mags.
I don't have a problem with them, I think they are cool. But I a can understand how someone would find them offensive. No woman should enter the men's bathroom? That is completely irrelevant.