That looks about right. Seems like your market pays $3/pickup + $.50/mile. You only get paid for the distance between the restaurant and the customer, not between you and the restaurant.
You're averaging almost $10/job, which is about right for GH. The trick is figuring out how to average 2 jobs/hour, not 1.
IF & WHEN GH decided a to cover the trip TO the restaurant, THEN I would consider joining GH.
You ARE getting ripped when GH doesn't cover that trip travel expense. Conceivably, you might travel 10 or more miles per shift & unless you have a Prius, that gas cost can really hit you when you have < 2 trips/hour