We normally go in by parking at Binion's and walking through to the canopy area. I wonder if they were screening that as well? We go down there all the time and I've never seen them do that except when there's a special event with an entrance fee. Seems to me to be a public street but I'm not sure myself how it's designated.
I do know that we went into the container park and it's a no-carry zone in itself (though totally private).