Kia Soul Fuel consumption MAJOR PROBLEM

I bought a new Kia Soul 1.6 in September 2013. Since the 1st service, I've been asking Eastrand to look at this vehicle's fuel consumption - 8.2 or 8.5L / 100Km! That's on economy mode too! They claim that's normal - but this is not how the car was sold to me. On a full tank (40L) driving to work and back daily, I'm lucky if I get 400Km on the tank. This is ridiculous. And Kia just don't give a hoot. HATE THIS CAR!!!!!