WalMart sells nothing but "sporting purposes" firearms. They don't sell handguns, and they don't sell ugly black guns. They sell shotguns, but not the "serious social social purposes" types. (except maybe via catalog sales, and even there they don't sell the UGBs, and while they once sold handguns through the catalog, I don't know if they still do). They sell .22 squirel and plinking rifles, and various sorts of "deer rifles" (or shotguns in some areas). Of course those "deer rifles" make dandy sniper rifles, and a hacksaw will turn a sporting purposes shotgun into a serious social purposes shotgun, get too carried away and you make a National Firearms Act short barreled shotgun. The .22s would be useful for shooting rats.
They do sell handgun ammunition as well as ammunition chambered for UGBs.