That, and perhaps also in denial about how bad flood damage can be.

We had a couple roads destroyed from major buckling as they were undercut by flood waters here in PA not long ago, and I know a region in Vancouver was left with no outside road access at all due to flooding recently - they had to airlift in food and medical supplies. And of course mudslides can carry houses with them and destroy fields as well as other infrastructure. Local closed loop hydroponic installations are a Good Idea(tm) for building regional resilience, but I only see them being discussed for their commercial viability thus far.