It costs more because houses are heated by a very simliar thing, fuel oil. Fuel oil can be taken right from a tank of a house and pumped into a vehicle but it is dyed in case the fuel color is ever inspected (pretty nice fines so I hear). Notice how most of the year it is cheaper until winter. If you run a farm the current price of diesel is about $.90/gal, good ole road taxs in my favorite state.
