When I worked as a valet in college we were instructed to park the nice cars up front (SUVs excluded since they blocked our view out of the lot and the general public's view inside the lot.) There was one guy who rolled in an NSX and never tipped more than a buck but his car got the front of the lot every time. Some context: we rarely parked anything much more exotic than that. I think what people have been saying here is correct. Big tips get you fast service and only sweet rides go up front. A good tip never hurts in this respect, either.

yorock