Unless you are in the habit of going inside and asking every time you get fuel, you've probably filled up many times just after the tanker has left without knowing it.

Seems kind of paranoid to me.

__________________
'11 335d M-sport/Le Mans/Oyster/Glacier/Titanium angel eyes
Lifetime avg fuel economy: @27,000 miles, 35 mph, 28.0 mpg

Pollution is bad, but carbon isn't pollution!