It's more that, while acknowledging that both would be important, in this completely contrived scenario where you have to choose only one, which one would you choose? In a world where your greediest next door neighbor is free to choose guns over canned goods, do you choose canned goods, only to have them taken away at gunpoint? Or, do you choose a gun and go find someone to take canned goods from? Again, a ridiculous thought experiment in the first place.