I've seen this before....its a wet bathroom, which means it's water sealed with sealed electrical outlets and extra drainage. You can take a hose to the entire bathroom to clean it. That's why there's no shower curtain, since it isn't needed. It's kinda overboard, but people with money seem to like them.
I don't really see it as overboard. People in Japan (and elsewhere) have wet rooms. I'm a fan of them, cleaning is easier and additional protection from flooding. It's the exact opposite of carpet in the bathroom.