Sorry, the system won't let me reply on my original thread. I get that different bands have different camera policies, but presumably they tell you in advance, right? Not the night of the show?
If that's the case, why not post restrictions ahead of time on the website, either with the show information or on the ticket-buying page (whatever's easier)?
Seems like it would free up your staff from having to take up so many cameras (lots of people just wouldn't bring them) and also from cranky fans...
Also, as a side note, I was curious about the distinction between "professional" and other cameras. Is that something the band specifies or a general 9:30 policy that you don't allow professional pictures? Just curious.