That's like being cut off at a bar. But that might be effective on one casino, but a real addicted gambler has many accounts on many casinos, and he will just move to the next one.
Yeah, and they'll be not allowed to enter for a period of time and when that time has already expired, they may enter again. And if they break the rule during the period that they're not allowed to enter, we can't stop them because they will think of some alternatives too.
In truth, there's nothing you can do except lock him up (physically)
Completely cutting them off. This is all truth and we can't do anything to these keen gamblers and addicted already. They'll reinvent ways just for them to be able to gamble too. Even with all self exclusion and other features and contingencies, they'll do it if ever a lot of hindrances have been made.