back-off vs barring
I think Flash's answer was right on (being conservative). But if they just said "no more blackjack" then all that can happen if you go back is to get backed off again or barred this go-round. Of course, you are going to be too smart to go back to the same dealer / pit crew, right? :)
If they tresspass you, stay away, as then you can get into great trouble with the _real_ cops, as opposed to the casino 3-stooges group. I'd personally feel pretty safe in going to _another_ property unless they specifically told me to stay off of _all_ of their properties. And they'd have to explicitly enumerate them to you to make it stand up I believe, as I have no idea who owns what most of the time, and just go to play BJ.