Because if you lose enough, you start dragging your family or community down. If enough people lose enough, they turn into a humanitarian crisis. People are social creatures, and want to help each other, and set up systems that do so - which then get unintentionally exploited by risk takers.

So a bunch of people do something obviously stupid - like getting scammed by a tech support call, or get infinite debt on a payday loan, or put a hand in a moving machinery and lose it. Now they're there, scammed, without money, and/or a hand. What are you going to do? Deny them healthcare and basic support? No, we help them anyway, and instead chase scammers, put limits on payday loans, and enforce safety requirements on equipment - we take away the choice of being stupid, because that's more reasonable than being indifferent to the suffering of victims of their own stupidity, for the sake of enforcing a corrective feedback loop.