Why is the pop culture in Japan so unusual?

So I'm learning about Japan. Cause I need to if I want to be going to Japan. I mean you can't just go to Japan and only know how to speak the language and nothing else. I think that's pretty dumb, but getting to the point. Why is the pop culture so unusual? From the commercials with the banana man to the toilets that look like ladies. Some of these ideas are cool and some of are... as if some one on drugs made them. I still think Japan is a great place because they're so polite and yet so creative. But yeah. And I want an answer from someone who's actually been to Japan for more than a few months. Not some wapanese. I hate it when people think they know everything about one place and they've never been there or stay there to little.