I can walk out of my door with a $100 dollar bill, buy a gun (sans serial numbers) and be home before the 5 o'clock news. There's a problem with that.
I think a the concept of a store that sells nothing but guns is as ridiculous as a store that sells nothing but poison.
I get it, guns are cool, they're fun to shoot, they make you feel powerful. I can even see how carrying one would give you a sense of safety but can you imagine, with human nature as it is, if EVERYONE was walking around with guns? There would be shootings constantly! There would be gunfights over traffic accidents, seats on the bus, wrong order at mcdonalds.