It's the nature of evolution in a car guy. How many if not all of us have put more time and money into a car than we get back in a monetary exchange. It's all really more smiles per gallon than the miles.
Which is exactly why I don't like building for fuel mileage. Doesn't mean it has to be a fuel burning pig (and that definition has wiggle room in it) but the more compromises you put into the build, the fewer smiles you get.
You need to set reasonable goals for power and mileage and go have fun.