Well, just so we're clear, I'm not advocating cannibalism.

If you're packing heat and ammo, and you have the energy to slaughter the townsfolk, there's only one other thing to make sure you have. A stew pot and the means to light a fire under it.
Of course, if its just a disaster and not the end of civilization, its going to be embarrassing (to say the least) when the cops and the Army show up and you're standing there. Next to piles of clothes, shoes, and polished bones