Okay, I'll agree to that one but it will be a remote option. You don't just wander into a small town and say "I'm here to survive do you want me?" especially AFTER the disaster has gone down.... Small towns just aren't that trusting. Ask folks who've moved to one even in the best of times. Folks are nice enough but you're ALWAYS an outsider even sometimes after 20 years. Anyway, just so long as you agree that the Jeremiah Johnson scenario isn't viable for long term survival.
Don't discount the value of short-term survival.
On the contrary, it's critical, especially if the disaster is also short lived. But in the proverbial 2012 TEOTWAWKI scenario or more accurately in the Luicifer's Hammer plot line (read the book by Larry Niven and Jerry Pournelle) where it's not assured the world will end, but it's not coming back full strength for decades.... the preppers have it cold.