15. I Didn't Say Anything About Guns (I don't even own one)
The OP'er's sister asked about food storage and emergency supplies. Good things to have.
Most normal people have candles and flashlights and enough canned food to tide them over a few rough days. Some of the richer ones have generators and enough gas to get them through two or three days.
If the "Big One" hits, it will take more than a couple of days for anyone to remember that our little mountain community exists.
The roads would likely be impassable for some time, since the San Andreas fault passes through most of them.
We keep enough food on hand to last more like a month. Some of this would likely be shared with less-prepared neighbors in such an event.
We have fairly frequent power failures. When a tree falls in the forest, our power goes out.
The longest lasted a week. We have a generator. During the longer power failures, that gets shared too, enough to keep the neighbor's freezer from defrosting.
What's totally wacko is trying to prepare for a full cultural meltdown. There is really no way to prepare for something like that, no matter how many guns you have. At some point, you're going to need services from somebody else and that's going to cost you a lot if you start out by pointing a gun at him or her.