Slate Auto, the electric vehicle start-up backed by Jeff Bezos, is a grand experiment in whether austerity sells ¡ª and a warning for the U.S. auto sector.

Slate recently unveiled its flagship: A barebones, two-seater, battery-powered pickup starting at just under $25,000. It is a gray riposte ¡ª complete with hand-crank windows ¡ª to the spiraling cost of new vehicles, now more than $51,000 on average. Buyers can customize this blank Slate with myriad options. Using the online builder, I quickly put together a truck with a delightfully retro ¡°Sun Seeker¡± wrap along with upgraded lights and wheels, audio speakers and an EV charger, among other things, for an extra $7,000 or so.

That figure also happens to be roughly how much people pay, on average, above the base price for the 10 best-selling SUV and sedan models in the U.S., according to Cox Automotive. Americans apparently clamoring for cheaper vehicles are also paying over the odds for upgrades. This seeming paradox doesn¡¯t end there and understanding it is essential to judging where the U.S. auto market is headed.