The whole thing is symptomatic of the "cut corners and dump more on those in uniform." Cars should be washed by someone employed to look after cars rather than someone whose job is something else, regardless of rank. There is an entire civilian industry based around car washing, valeting and servicing and someone employed in this role will wash the car to a higher standard than someone back from a meeting.
Perhaps this is something to do with civilian contractors cutting corners and overheads to bump up profits...