First, he's guest posing. He's not going to get up there and do quarter turns. Second, competitive BBing is never going to be in the mainstream. BBing had Arnold and it still wasn't popular!
He's probably one of the very few pros actually getting paid good money to be a pro and it's because he is entertaining and making a scene. Draw a crowd, get a lot of cash. If it's ever going to be more popular than it is right now, it's going to be via guys like Kai.