...The AV trivia included here makes me think the Japanese are so GODDAMN WEIRD in their tastes. I mean if those types exist it's because enough people has that same tastes to bring in a profit, right?
I like to think of it as people naturally have myriad tastes and the Japanese are willing to cater to all of them, out of mutual appreciation and a sense of service (within reason and behind half-closed doors).
While elsewhere, everyone has something 'weird' they like but tend to bring it to the grave with them. I think there's some irony in that the Japanese, in keeping different things private by distinguishing between their public, private and even more true selves (go look up the 3 faces concept), can be more honest with themselves than other cultures when given the privacy to do so.