TOOL has a "no camera" policy so fans can't take photos or video during shows. It's on the tickets, all over the arenas, and it's even emailed to people who bought tickets.
The notice warns that fans will be EJECTED for pulling out their phones. And they say that if there's a personal emergency, you are allowed to use your phones on the concourse, AWAY from the performance area.
It's unclear if a lot of fans are ACTUALLY being thrown out of shows, or if it's just more of a threat.