If someone damages your car while you give them a ride, YOU have to pay for repairs. You have to pay for gasoline, oil, tires, wear...
There is no guarantee that you will get enough ride in a night to make it worth your while. There is ALWAYS a possibility that you will be taken far away from your covered area, which means you may have to drive an hour OR MORE, between a long ride (no tip, because the ride is "too expensive") and your next.
work when you can, meet ssome nice people
wear on care, out of pocket expensese, drunks, stoners, rude people