The biggest problem with limiting what people purchase with food stamps is do it. It would just limit what the pay for with food stamps. It would cost the tax payers more because there is no savings in limiting what people buy with food stamps. How much would it cost to pay for the limiting process. How much of your tax money do you want spent on enforcement. Do want a unfunded mandate by the goverment telling private business to be the enforcers? They already do for sales taxes in many states. I would assume most people using food stamps also spent cash. I have seen people sort their items by food stamp and cash items. In a larger market the clerk can say the registrar would let me take a ebt card for that. But in smaller stores you making the clerk the enforcer for the goverment. Would you be a goverment enforcer. If you would be a goverment enforcer would there be a line would would not cross?
The problem is the program is geared to buy votes and make people dependent on the goverment. I would address the problem with the goverment first.
Eliminating food stamps would eliminate those problems.
Give them food, not food stamps.
It would also eliminate the vote buying.