Probably just trying to figure out if his own car is a bit thirsty or not.
Darn in Kent the term is juicy mate very juicy when asked what their car does to the gallon, or the other answer is, doesnt go far on 20 quid
I asked our new workmate who commutes 43 miles each way what his mpg of the diesel Focus was, his answer? dont know! come on you are doing 400 plus miles per week you can be very accurate without even trying?