Your food stamps will not buy you a Vanilla Bean whatever with whip at Starbucks. You can try, but your card will not work. You can slide your card again, but it won't work the second time either.
They will not buy you a hot sandwich at the deli. If you order a hot sandwich, and then are told you cannot use food stamps to pay for it, you either pay for the sandwich or you have to forfeit the sandwich. The cashier will not ring it up as a cold sandwich "so's you can use them stamps".
Can't buy beer. Or cigarettes. Asking the guy in front of you in line if you can pay for his stuff if he'll "buy you some cigs in trade" is called welfare fraud. If I knew your name I would report you.
Take-n-bake pizza? Sure thing. As long as you take it and bake it. At home. If you have them bake it for you, you forfeit the pizza. Take it...and bake it.
Food stamps are for food items, people. Food. Not diapers. Not aluminum foil. Not birthday candles! Yes, I know they're to put in the cake, but a candle is not a food item!
Following these simple rules, guidelines even, will save us all some time in the checkout line.