Where in the US is there a supermarket that sells guns? I've never seen one. They'd need a FFL (Federal Firearms License) and anyone purchasing would have to go through a background check and in some states, a mandatory wait period of 3-10 days.
A large fraction of US Walmarts sell both groceries and guns, to name one example. I suspect this correlates with the states that don’t impose a mandatory waiting period, though I haven’t checked.
