My irrational (?) fear is not necessarily for other's troubles, but for my own. I am not "mega-prepper", but I am better than the average Joe. My fear is to not have something I need (maybe I had it, but ran out of it during the disaster), and not be able to fashion a suitable replacement.

When I look around me at all the simple things I depend on daily, I often wonder how I'm make something like that myself. Say, even my cereal bowl. I suppose I could carve one out of a block of wood (that would take me a full day). But to do that carving, I'd be looking for my knife. But what if my knife was gone? How would I make one of those? It's not like we're just rolling in flint deposits here in the suburbs that I could knap something out of (assuming I knew how to knap something in the first place). I could probably learn how to knap through trial an error. But there goes a week of my time trying to learn that. By the time I had made all the things I needed to make in order to make other things, I would have died of starvation from my missing cereal bowl.

That's my irrational fear - the snowball effect of missing items, combined with my personal incompetance at making them myself!