I know you’ve gotten a lot of replies but i thought i would add to this.
My career track before my current one was as a mechanic. It wasn’t very long, because while i love working on cars, the way the pay worked as a mechanic, it sucked. I wasted a lot of college tuition and time figuring out it wasn’t the job for me.
Anyways, when i was training, i worked at a medium volume dealership under a master mechanic. I have a hard time believing people saying that the GM and service advisors don’t know porters do this stuff. While its against any dealers policy, and the insurance companies frown on this, everyone at the dealership knows this happens. It was part of what i hated about working there and why i don’t take my car to a dealership unless i have to.
We had one porter who went to get lunch after he washed someone’s car at our dealership. He drove approximately 2 miles to the fast food chain. He ended up getting stopped for speeding and got arrested for having a warrant and he didn’t have a license. The cops towed the car and it cost the dealership a lot of money to make here customer happy after the incident and the customer told the service advisor they were never coming back. They also had to have a body shop repair some paint damage from the tow. They ended up not firing the guy, and he continued to do the same thing. Not sure if he ever got stopped by the cops again.
So to everyone saying this is acceptable or something the original poster shouldn’t be worried about, you’re wrong. Even a short trip can result in something like this. Your typical porters are people who are just doing a job to get minimum wage. Many are great people, but there are also a lot who don’t care about your car and treat them that way.