When you take off ... Don't plant your foot
Nah, could be many subtle differences in driving style, how many cars over taken, how many stops and starts etc etc
May be a fuel filter, air filter.. Sensors etc etc..
I get around 14.5 town driving per 100 k and.. On the highway down 9/100 that is outstanding in my book.
However, I'm not that concerned, if I was I would not have bought this type of car.
I just drive it.. And fuel up, whenever it need it