I'd add again that human societies adapting to a zombie apocalypse are actually very nearly the norm right now: there are fewer and fewer films/books about the actual apocalypse, and more and more about how we'd manage to survive. It's a really interesting phenomenon. I only listed a few in the post above, but there's far more than that. The tagline for Walking Dead is something about it taking the end of the world to learn how to live; that alone implies that the series is about survival and adaptation.
I wonder how much of our real life economic disaster plays into people's appetite for fictional disasters and how to adapt and survive?
On topic: I as well that it was a great episode.