It feels like banning advertising for gambling would be a sweet spot between harm reduction and maintaining individual liberty. Sports gambling ads have ruined sports media. State lottery ads are even worse. The government should not spend money to encourage its own citizens to partake in harmful activities.
Nah the sweet spot is to make the gambling companies pay for the treatment and recovery of the people addicted to their products, up to whatever amount they gave the gambling company.
Food, tobacco, alcohol get more interesting... As there is bit harder time to assign blame of each meal. Maybe in those cases the claimants should be able to fully list everything they have ingested over say past 10 years. So that liability can be fairly and exactly distributed.