In my opinion, there is a difference between receiving a payment directly from a casino's address or receiving a coin that in the past has been withdrawn from a casino.
The former is normal business procedure: some businesses are simply not allowed to receive a payment from a casino, be it in crypto or fiat. That's nothing new.
Bitcoin is supposed to be electronic cash. If I get cash from a casino, there's no way anyone can know, and nobody is going to refuse my cash for that reason. Ideally, Bitcoin should be treated the same.