My counter-point to this is simple: it's easier to make make-shift explosives from kitchen supplies, than it is to legally carry a gun around. The most abundant weapons are not guns, but various types of knives and axes. You'll get into less legal trouble if you beat someone with a stick, than if you shoot them. And finally, even soldiers, who usually have guns, are trained to bash their enemies with a shovel if necessary.

This assumes the PCs are not professional soldiers, law-enforcers, or criminals. And even they need stats for knives, batons, blackjacks, unarmed combat, shovels, pepper spray, tasers, artillery, bazookas, grenades, mines etc., for those times a gun won't cut it. Perhaps literally.