I have caught a number of people on tape taking NCV's.
Several were still in the room. I just walk up and ask for them. If they deny it I call security. They are pretty quick to give them up at that time.
We caught several at last June's tourny.

If they are gone, I just wait for the next time they come in and have them trespassed warned from the property.

You would be surprised at the number of people caught at different LV properties including a couple of club members.