IANAL but there are a few things in this matter that seem to be common knowledge. How these things will apply to a specific instance is for lawyers to discuss. The law, at least in Nevada, does defer to the casino's right to do business with whomsoever it chooses. The law does not permit the casino to beat a card counter up (like in the movie "Casino") but they can insist that such a customer leave and never come back, and in those cases at least in Nevada, when such a customer tries to return, they may become a trespasser [1].

[1]http://www.pandullolaw.com/Criminal-Defense/Trespassing.aspx