[bumby]

>when station wagons were a thing

Just some interesting context, the original SUVs were station wagons. The big Suburbans/Wagoneers/Broncos/Blazers of the 70s and 80s were classified as station wagons. In addition, many of the station wagons back in the day got horrible gas mileage (many had the same engine size as their SUV counterparts).

Beyond that, the idea that people would be choose to have multiple cars for different aspects is a bit out of touch. The majority of Americans can't spring for a $1k emergency repair, let alone have another car payment just for a grocery getter. Most people need one car that can do most everything they need. Even if they could afford more than one car, your premise doesn't make sense. How many miles would have to be driven for a $20k used car purchase to have a positive economics based on its fuel savings?