Well you know - I live in Europe (more specific: Poland).

No food reserves - right. But why ? Part of it is its costs(especially in central-eastern europe it is the issue), another part is "common sense" or rather brainwashing doing its work as many people are brainwashed to believe "government will help you" and such shit - what is the case about Germany and any western Europe countries.

And about building on flooded areas. u/JollyJocker probably don't know how big problem is corruption. In theory there are state regulations. In practice however developers build what they want where they want,they have just to bribe some officials.Also in western Europe,also in such Germany.

But yes,you are also right many people are indeed idiots who would buy cheap place near the river too. Well there are funnier situations, some idiots are building near airports, racetracks, on villages, near shooting ranges and complaining about natural things that surround them. So sometimes farmers are forced to stop farm,racetracks and shooting ranges are closed and so on. Because "muh democracy" (rather ochlocracy or idiocracy).