Dazz, you should consider yourself lucky and fuel economy isn't the only reason for this
Well, unlike city, I'm happy with economy when driving out-town.
Last summer on our way back home from our vacations (with wife, 2 kids and a full trunk) i was travelling at ~150 km/h for the first 100 km on the brand new "Ionia Odos" and even reached 180 km/h -on GPS- a couple of times.
Consumption was stuck at 8.0 l/100km which i think is fair.
Then i heard on the radio news that gas-stations were on a strike and that there was a problem with the fuel replenishments. I decided to slow down, so i kept a constant speed of 90 km/h for the next 300 km.
I noticed that consumption on trip-computer was falling and falling and... by the time i was entering Athens, consumption dropped at 6.0 l/100km!
This makes me think that consumption at 90km/h with a normal load should be
well below the 6.0 l/100km (*)
Unfortunately, car is used mostly in town and considering the economy in this case, isn't what i call a town car...
I'm curious to see if anyone "managed" to read 10,9 l/100km on his/her trip computer. Drag-racers and whoever has a brick instead of a right foot, are excluded
(*) that said, you didn't have to buy a Hybrid for Tassie