It's exactly the same thing. Flood insurance enables people to build houses in places where there are going to be floods, just like fire insurance enables people to build in tinderboxes. Which would be fine if the person who buys the house there carried a financial burden proportional to the risk.

there isn't a ton of flood preventation infrastructure that has been built with tax money.

All flood prevention infrastructure outside of the dirt berm at the local pond was built with tax money. Been to, say, New Orleans recently?