I'd like to point out that this is nothing new when it comes to boy bands.

The Beatles is probably the greatest example of this kind of fanatical behavior of their fans. And YES the Beatles WERE a boy band. Lots of songs about girls, love, etc. Only difference is that Beatles continued to grow and change with their audience, while most boy bands of now are simply dropped by a record label for the next "best thing"

Regardless, apparently this kind of behavior got so bad in the US they actually either stopped making concert tours, or simple didn't have public appearances outside of the concerts. I can't remember what I read.