Aid for rebuilding after Sandy

In the aftermath of hurricane Sandy, the US federal government and the northeastern states are currently wrangling over the amount of federal aid to be provided. The news last night reported that some fraction of the proposed billions of dollars in aid would be used for rebuilding homes, and the rest for rebuilding businesses.

It occurred to me that homes on which there is a mortgage are generally required by the lender to be insured for replacement value by the title holder; that’s certainly the case for me. Given the value of my home, I can’t see myself reducing or eliminating my homeowner’s policy after I pay off my mortgage. All of which leads me to wonder, who is the aid for?

Questions:
-what percentage of homes in the US have a mortgage on them (and so are highly likely to be insured)?
-of the homes which are owned free and clear by the the title holder, what percentage of them are uninsured?

Same goes for businesses, I guess:what percentage of businesses are insured against loss of property (and loss of business while rebuilding)?

According to the US Census Bureau, approximately one-third of all owner-occupied homes are owned free and clear. They don’t say what it is for rental units or who has insurance or not. One thing to keep in mind is that many of the homes suffered flood damage and that generally isn’t covered under the usual homeowner’s policy that most people carry.