We have a backpack full of canned fish, canned meat, almond butter, lara bars, fruit leather, and dried fruit. We live out in the boonies, so if we get snowed in, we want to have food to eat. In an emergency, we could evacuate with that backpack. It's rather heavy, but that's what I have Knifegill for, right?
It's also good to remember we can go a long time without eating, so a fast isn't too terrible (though worse for little ones). Also, a week or two of eating junk won't kill you in the long run, especially if you're burning it off. Though, if your have real health reasons (celiacs, for instance) not to eat gluten or an allergy to the junk in processed foods (which is what they'll give you at shelters), then make sure to stock up on your own dehydrated jerky, fruits, pemmican, and canned foods--just to be ready!