Look up charts for wage development and minimum wage on one side, and charts for CEO pay and gini coefficients (wealth distribution) on the other, over the last 50 years. There you have the answer why a working class person can only afford crap shoes and beater cars.
The boot theory is nonsense that at best only applies at a pretty narrow range of consumer goods - stuff that is barely fit for purpose vs stuff that is.
Cars are a great example because you pretty much can't save money spending more up front on one new car than on another new car, and there isn't even that big a difference in TCO between a new car and a comparable five-year-old car.
Working class people in the USA buy beater trucks to save over buying a new truck, which is a different trade, mostly because trucks are a working class Veblen good. They don't want to be seen in a Corolla.