I agree this looks bad - like someone who is banned from a bar still being served as long as he has enough cash. I don't think a casino has a duty to pre-screen all its customers before the betting begins, though. It's only when they become "visible" to management that the screening begins. It might be because of trouble, or a credit request, or a jackpot.

I'll bet (pardon the pun) that (1) the casino will not face liability in court or through the gaming commission and (2) if word gets around (as it should), betters who voluntarily place themselves on the "ban" list will learn that there is no way they will be able to win, so they should just stay away.

People don't put themselves on the list because they live too close to a casino. The lists are offered as a response to government regulators to show that casinos are "genuinely concerned" about problem gamblers. Feeding their addiction by paying the jackpot would violate that pledge to regulators.