I agree with you 100% that they remain property of the casino and the casino can ask the player to cash them in at any time. I was just questioning whether it was ILLEGAL for a player to remove chips from a casino, which was the original question.

Not to beat this to death, but don't some high rollers remove racks of chips to later bring back to the casino to play with or cash in? (I'm thinking of some TV program that showed Bob Stupak bringing a rack of chips back to someplace he played.)