Your probably referring to the Autobahn. I asked a German if people drive really fast on the Autobaun. He said, "No. Most drivers are trying to save fuel" .
I can agree with the fact that people are driving slower here, especially in the winter. However, during the summer the left hand lane is moving at 90-95 MPH on average (when there is no speed limit). There are definitely people who surpass that, especially on motorcycles.
I think when I drove pass the gas station today it was 1.53 a liter (5.78 per gallon).
You have to remember though, Germany's public transportation system is superb. You rarely need a car to get from point A to point B. The only time we drive is to the grocery store for the most part. I spend way less money while I am in Koln compared to when I am in the Bay Area. If we still had the Audi I would drive on the Autobahn for pleasure only, realistically.