How about this: no-one gets charged for calling an ambulance. If the crew judge you to be genuine (guidelines would be needed, obviously, but generally speaking any of the following are genuine, in my humble opinion: anyone requiring immediate treatment from the crew, anyone with a disabling injury, anyone with mobility problems preventing them from accessing treatment by other means. Not an exhaustive list, just the first ones I thought of). Anyone "non-genuine" can still travel to hospital by ambulance, but will be charged a reasonably significant fee for the journey. Up front. That way, no-one (low income, elderly, etc) has to worry about being charged for calling a truck, but we would not end up being used as a free taxi to hospital. I think a similar system operates in some parts fo Canada, unless I dreamt about that...