It doesn't have to be a prohibition either. Advertising could be banned. Branding could be controlled so it isn't appealing (Provider 1, Provider 2, etc). Parlay bets and "innovations" (which burn customer money 10 times faster) could be restricted. The "concierge" service that preys on the big spending addicts could be regulated/erased.

That's the sort of ban that actually works for society, because it is strongly focused on disincentivizing harmful behavior, while shutting out the black market.