I picked up my car 5 weeks ago with 7 miles on it. If there aren't any gas stations near the dealership, they will need to put more miles on it. Plus, I assume they need to test drive the car during their preparation.
It seems like some dealers prepare their cars perfectly and others do not. My car is black sapphire and I read many threads warning about dealers putting swirl marks in black cars. I bought my car from Sonnen BMW in the San Francisco Bay Area and they prepared it perfectly. Plus, I had a great SA (John Daniel) that made sure everything was done properly.
I walked around my car, checked it out carefully, sat in it, checked out the interior, signed the papers and drove home. I love it.