Here are a few of the reasons why it just makes sense to be adequately prepared for disasters:
This article takes a look at the price gouging that Hurricane Sandy survivors who were not prepared have to deal with, such as ten dollars for a box of matches.
Jennifer Merritt wrote this piece about the realities on the ground for the people affected by Sandy: “Nearly a week after the storm, residents saw the first power company crews walking the block. The crews, while sympathetic, said they had no way to know how long it might be before power could be restored.”
Finally, the NY Daily News ran an article about the ongoing fuel shortages in the area: ““We’re not 100% sure when the system will be up and running where you won’t feel any effect whatsoever,” Cuomo said.
sets out a generic plan for dealing with disasters, based on the concept that all of these events share many of the same basic challenges. 
72 Hours Is Not Enough
Eric Holdeman pointed out a conclusion in a recent article that gets increasing support with every large scale disaster we face as a country:
“Years and years of drilling into people’s heads that they have to be prepared to be on their own for 72 hours or three days has provided a negative learning experience. When bad really is bad, three days is not enough. Here on the West Coast which is earthquake country a week is the minimum that I’d recommend. There is no time to pre-assemble disaster supplies. These are “come as you are” disasters with no warning whats-so-ever.”