Some jobs are harder than others, and deserve to be rewarded more than others.
So, shit shovelers and IT professionals should make the most money? Works for me.
You don't see people selling cars with "up to 40mpg", then you only get 5mpg in normal driving conditions.
Where the hell do you live? I have never seen a car get anywhere near what the manufacturers claim for mileage. Admittedly not a 35MPG difference, but I am sure you could manage it, if you tried hard enough.
In a test I did myself, I was able to get close the the claimed mileage, but only by driving and accelerating so slowly that I am sure someone would have run me off the road, or shot me before long.
If you want to put yourself on the map, publish your own map.