I always wondered that too. Hats can be really expensive, have strong sentimental value, or be broken in just right after years of good use. They ought to have some sort of collection area after the game. Maybe link it to a $10 donation to the team or league's charity or something.
probably. i threw mine back in 2001 when newy got one on new years. just told the ushers i threw my hat. had to describe it at the bind. got in back. no big deal.