To solve many corner cases, you could maybe have a kind of voucher application at the grocery stores, gas stations, car mechanics, etc., which would provide a temporary advance (or just money from a designated separate emergency or unusual circumstance pool so that it isn't like a credit card) which would need various rules that would guarantee that the service provider would always see the money, but also ensure that the applicant would be registered and held legally liable for misuse of the voucher system.
