Let's say that every unit of time spent driving a vehicle is of equal utility for every person, and that the utility scales linearly with the absolute length of a given stretch of driving or time between. Let's say everyone uses their car to go basically the same distances to the same kinds of places carrying the same cargo and passengers, with basically the same costs for needing an alternative. Let's also say that cows are frictonless spheres in a vacuum.

Or we could just not pretend that "utility" is a concept that can be applied uniformly across all car-shaper objects.