"Your reservation is non-transferable. Any attempt to a s sign or transfer your reservation will result in the cancellation of your reservation and return of your reservation fee without interest." As per MY reservation confirmation.
As I understand this, it stops being a reservation once you BUY the car. Then you can sell it. It doesn't bother me one way or the other as long as I maintain my place in line. I'm sure lots of people will pay more to have theirs first. Just the fact of the grey market prices proves that. For the right price I'd sell mine, too. As Fred says, it's just a car.