True, but also, recent disasters were "freak" ones. Flooding on this level has never really happened in these areas before. A lot of the homes destroyed didn't require flood insurance (homes in the standard flood planes / hurricane areas do require that the owner have flood insurance)

When your town looks like this, https://www.youtube.com/watch?v=0ZSXGin-zNA , and the fire department is fully underwater, the locals with boats win on quick response time. (Followed by disaster-specific response teams like the coast guard, etc.)