It's not entirely about killing and maiming. In GTA: San Andreas, there are missions involving driving a fire engine and putting out fires, and (I think) driving an ambulance as well. Although I'm pretty rubbish at controlling the vehicles so end up running people over anyway. :/

The ambulance needs a delicate touch, but given that the fire engine is like the fist of God that's pretty much the best way to get it around, anyway.