Early on, one of the experts said that malls are typically full of unarmed civilians, or some such. Was this his way of calling them victim disarmament zones? Probably he was stopped from saying just that by a PC producer.
This is why more law abiding citizens need firearms, so that when stuff like this happens, you don't have to set up a makeshift ambush using whatever's in a store (which varies, a lot). You have your gun that you've practiced at the range with.