> Average American household budgets are dominated by [...] transportation
Huh? Doesn't the average American live in a city? The whole reason for accepting being squeezed in tightly with other people is so that you don't have to worry about transportation; enabling everything you could ever want and need to be found in short walking distance.
Transportation is for people in rural areas. Yes, it is expensive, but that's exactly why most people left rural areas for the city long ago.
Most American urban areas are dominated by suburbs where it’s not practical to walk everywhere and public transit is very limited. So a car is necessary and often a car per working adult.
This is an "urban" home in a "city" of nearly 40,000 residents. Good luck telling this family they don't need to worry about paying for at least one automobile.
You've been mislead by an overloaded term. Urban in an academic context is a much lower bar than urban in a "any reasonably layman's meaning of the word" context.
Pretty much any time you hear "city" or "urban" it's either a direct or indirect reference to US census data (or follow on research by other academics that uses their definitions) which play fast and loose with the word urban in a way that results in the population of even the most far out municipalities within a city's economic area being countable as urban in some capacity depending on what data set you want to use (some of the data sets draw economic distinctions rather than lifestyle ones, so a rural farmer who exists in the eoncomic gravity well of a major urban area will be counted as urban).
This is all magnified by substantially less than honest people omitting the potentially misleading nature of the term when it suits them and the people who they've informed going on to parrot it without actually understanding it.
INB4 nitpickers, it's been a decade since I've done any work with this data, if my knowledge is out of date and it's no longer misleading to the layman then good.