Beer at a rest stop in Mississippi

I'm familiar with beer and wine being sold it grocery stores. Sure, in Pittsburgh and New Jersey, two places I've lived, that's not the case. But beer in a supermarket makes sense. Not sure about beer at a gas station out in the middle of nowhere off an exit on Route 55 S in Mississippi. Presumably, most people would be stopping here hike driving, and you wouldn't want to go without your individually sold beer can or bottle.