Thus, fuel prices have to be affordable enough for poor people, but a moderately wealthy person can tolerate to pay double that to drive the same distance. Those a little further up the hyperbola can drive four times as far. And after a few years of exponential growth, we all can.
I've been wanting for taxes and other duties to be exponential shaped. Scale property tax exponential with the energy use of a house. Scale vehicle tax exponential to the car's fuel consumption. (You could require airlines to charge a sort of negative-percentage frequent flyer's discount as a tax, but that would be communism.)
My guess is with the right parameters for base and exponent, this system could be very just, ensuring that everyone can fly across the country to visit family, but weekly business flights become prohibitively expensive. And my hunch is that this would be a more effective way to reduce total energy usage without creating disastrous living conditions for anybody.