Perhaps you are just not driving it as well as other people? The way you drive does not have to be scary to use up a lot of fuel.
Do you coast out of gear much (wastes fuel), do you engine brake up to lights, anticipate lights changing/junctions to minimise braking?
I was in a car with a friend the other day, and was noticing that I was feeling a bit ill, i then saw that she was continually slowing down and speeding up. She jabbing the accellerator with her foot like a switch. I asked her what milage she was getting, and it was appauling for the car (Diesel turbo citroen).
I informed her about the cruise control she had never used. Since teaching her how to use it, and a few other pointers she says she is getting 20-30% extra out of each tank. Big savings, as she is a technical sales rep, and drives all day most days!