many reasons... publicity, to make a statement, to earn a living etc. most musicians do it all the time. just look at that eminem dude for instance- there's this time where he curses his fans and wishes her mom killed on his songs, and then there were these songs when he kisses back his fan's asses and say sorry to his mom and shtuff just so that they'd buy his cd. It's a really strange world we're living in.