I'm not advocating selling heroin at the corner store. Perhaps it should be sold over the counter at pharmacies? A licensed pharmacist can advice the buyer of the risks and can connect them with resources to help with addiction if there is a desire for that.
We already massively promote and sell alcohol nearly everywhere. It's a deadly drug that is more dangerous to use than many illegal drugs. Tobacco is similarly broadly distributed, yet causes cancer and early death in millions of people.
If drugs were regulated based on their risk level, then it's likely that tobacco would be sold in plain packaging at pharmacies and MDMA would be available in a vending machine...