One thing that I think is frequently overlooked is that a person with a year's worth of food stored up also has enough to feed the whole neighborhood for a week if necessary, which might make a really big difference for a lot of people. Having the goods gives you a lot of flexibility and might take some of the pressure off of emergency relief services. I try to keep far more of the basic things on hand (first aid, food, and water purification stuff) than I think I'll need just because I know most people don't, and I live in a place with a moderate risk of catastrophic earthquakes and tornadoes.