What they dont know they dont know. Stuff your scanner in a big jacket pocket with some headphones and scan to your hearts content. Maybe go to the restroom of you need to change scan groups or what have you.
Absolutely not! I was at a ham radio convention there in the early 1970's. A ham used his handheld near at blackjack table for just a second and security came out of the woodwork to pounce on us. Those of us without radios were allowed to leave eventually, those with radios were taken into a back room. When we made the reservations, a group sales, they didn't say anything about it. The PD was called and eventually all hams with handhelds were released, with a stern warning to not bring them back at any time. If that was the situation in the early 70's do you think they are less strict today? The fact that the scanner is only a receiver does not make any difference. We tried to get an exemption that if we didn't transmit we could bring them in . . . NOT!!
What they dont know they dont know. Stuff your scanner in a big jacket pocket with some headphones and scan to your hearts content. Maybe go to the restroom of you need to change scan groups or what have you.