Suburbs, sprawl are subsidized by urban areas. By zip code, county, state, region.
Unless you're claiming that by working in the city and commuting home to the suburbs, people are being subsidized by the city. But that would be silly.
Not a claim. Merely a statement of fact.
You're missing in your equation:
1. Population density. If the population density is lower, the cost to maintain the infrastructure per resident is higher. The claim is that even though suburbanites are richer, they are not rich enough to offset the extra cost per resident.
2. A lot more businesses (and big businesses) in the city vs the suburb. This is a significant revenue stream.
I've seen maps and claims where even in the city, it is usually the downtown area that subsidizes the rest of the city (let alone suburbs).
No, I'm arguing in favor of higher-density cities with a mix of low, mid and high income under a larger governmental entity.
> If people still want to live in large houses in low-density areas, let them pay for it.
They did, though. I mean, suburbs are rarely directly financed by larger cities and initially, inhabitants of suburbs are, on average and in the United States, wealthier than their counterparts in the city (and nearer suburbs). The problem is that a certain class of people is only willing to foot that bill provided certain discriminatory characteristics are present. When those characteristics (such as racial segregation by means of socioeconomic discrimination via HOAs and zoning laws) fail to accomplish their purpose (the top-earning percentiles of those "undesired" classes of persons gain enough to love in, decreasing the desirability of the suburbs in the eyes of the people that initially wanted it, driving its prices down, allowing more diverse population groups to move in, rinse and repeat), those inhabitants that could moved on to other, wealthier and more exclusive suburbs even farther out.
The problem now is the suburbs in between, comprised of people "willing to pay" for the "status" of not living in the city but not able to afford it. You're essentially arguing to _increase_ segregation between the wealthiest and poorest striations of society, which would effectively redefine what it means to be middle class in America and possible wipe out the concept of lower middle class entirely.