I think its because he was in American Idiot. He got at least three times as famous. I was at the show and the only time the crowd went crazy was when they were looking to see where billie joe was. (I was one of them) Or when his name was announced. yes it may also be because he looks the best and is the most presentable as well. It happens with every band the front guy gets the most attention because they are the face of the band. Just look at MCR or All Things Lost, the front guy is the best looking and the fan girl fall all over them. And people(like me)jump when they see a headline with Billie's name on it. But I get where you're coming from.