I can understand telling the public they can't shoot them off but they shouldn't cancel the big shows put on by professionals. Every one I go to is conducted with the fire department on-site beside the shooters to handle any small fire that starts from the falling remains of the shells.
That's exactly the point I was about to make. Our fire department ALWAYS has an area set up where they are on standby to douse any fires that start. I get banning regular people, but the big shows can easily have safety precautions in place. We are under a burn ban as well but ours went on anyway, with the fire department on stand by as usual.
On a side note, I did have a grass fire that started in someone's backyard last night b/c fireworks in the neighborhood landed in their backyard.