That's interesting, maybe we adopted contactless payments faster in part because in our gas stations you'd usually pay inside the shop. I have to think that was only one of many reasons, though.
Edit: Bad googling, sorry. 57 mpg was proposed for new cars.
US gallons happen to be smaller too, fwiw
NB: the above mpg numbers are computed using US gallons (3.785 litres)
I meant, for anyone that missed it, that commuting by bus/train/tram/metro is much more common in urban areas in Europe than in the USA.