I'm sure that they all know about Katrina. The trouble is that many of these people have moved from an area--or maybe a better term would be a "culture"--where preparedness is looked upon as something a wacko would do, right smack into an area where you can expect catastrophic storms every other year.
I seriously doubt it's the native Floridians who are doing most of the whining. And FWIW, I'll bet that after a couple of hurricane seasons most of the transplants start storing food, water, and fuel. Not all, maybe, but most.
Regards, Vince