Why Doesn't Per Capita Energy Use Decline?

From "Our Finite World"

Carberutor engines in cars were phased out around 1980 and the average fleet fuel economy jumped from about 18 mpg to ~25 mpg and has increased each subsequent year as engineers eek more efficiency from engines. You can actually see that impact in the chart as transportation fuel consumption declined into the 80s (the oil crisis also killed off big cars and big engines) but it didn't really stick.

10 kWatt Generator

Supposedly industrial processes are more efficient now because of automation, and energy saving technologies, and various renewable energy technologies have seen wider adoption, but for the most part per-capita energy consumption hasn't dropped. In the US every man woman and child has the equivalent of around 10 kWatts (~13 horsepower) powering their lifestyle 24/7/365 even though industrial activity has been shipped overseas for decades and all the mom and pop farms and stores have been replaced by corporate entities that supposedly should use less energy because of their economies of scale, and perpetually increasing "productivity".

I've only really seen half assed explanations for this phenomenon.