Ok, my driver window started going off track this morning

so I took it in to the dealer who happily fixed it free of charge in about 1.5 hours.
That bothered me, but get this:
My trip meter was at 38.X miles @ 54 MPG. When I got the car back, it was at 38.Y miles, @ 38 MPG, and my gas bars dropped from 4 remaining to two remaining.
What did they do, keep it running with the AC on while they fixed it???
Sheesh.
Oh yeah, window works fine now.