[jeffbee]

I don’t know why you are posting these suppositions when the government measures this directly. The spread between the lowest and highest income quintiles in terms of motor fuel consumption is 300%.

“ The highest income quintile (making at least $95,000 per year) spent slightly more than $4,000 on gasoline in 2013, while the lowest income quintile (making under $18,000 per year) spent about $1,200 on gasoline. Higher-income households also have more vehicles: 2.8 per household for the highest quintile compared with 0.9 per household for the lowest quintile.”

https://www.eia.gov/todayinenergy/detail.php?id=20772