But a "safety net" enables people to take risks that work out positive for society. E.g. in the US people are much more willing to start a business (something that should be a net positive for society) once they pass the Medicaid eligibility age, since they can be assured they'll have healthcare even if their business fails. Heck, the joint-stock corporation, the big innovation of capitalism, is basically a way to reward failure (by limiting investors' liability in failure cases).

You do need to be careful about perverse incentives, but being homeless or unemployed is so bad for you that I can't imagine a few hundred dollars make it suddenly worth doing deliberately.