Why are food stamps (but universal, not means-tested) not a good solution?
They allow basics to have controlled pricing, and increased availability, while preventing abuse of the system (ie, alcohol purchases).
Having dispensaries (or dispensary-specific items in a general store) where you can use your food stamp money would leverage a working system we have now.
Food stamps generally do not allow purchasing hot food or a wide variety of foods that are not considered essential (there is some variation in policies, however). Remove those restrictions, and it would be better.
You would still have the problem that it wouldn't actually provide food for everyone or some people would end up losing the money because they're frugal.
What about people who are addicted (huge problem in the US)? If we give them money, they will spend it on drugs/alcohol/etc. and will still need to be taken care of.
So while food stamps (universal or need based) may not be a perfect solution (selling food stamps for drug money is not unheard of), it is still better, because it makes misappropriating the help provided more difficult.
There will always be a segment of the population who will take the benefit and use it to make themselves worse off.
But it doesn't matter because far more people will use it for good things like feeding and clothing their families.
On balance, that's better than what we do now, which is that the addicts still abuse substances, but many who are not addicts struggle to provide for their families.
They allow basics to have controlled pricing, and increased availability, while preventing abuse of the system (ie, alcohol purchases).
Having dispensaries (or dispensary-specific items in a general store) where you can use your food stamp money would leverage a working system we have now.