Suburban infrastructure is usually much more sparse, of lower quality and a lot of it is shifted to the local business/homeowner.
As an example - city water vs Water wells & Septic tank/fields. Gravel roads without sidewalks, etc.
So it's not 100% evident that cities subsidize rural counties. Cities do provide the larger tax base for states, which probably subsidize more rural counties through incentives tied to certain rural activities, but making a blanket statement is probably not accurate.
Towns and counties produce revenue from property tax and sales tax.
The infrastructure relies on state support, which is usually from Federal funds and personal income tax. That aid is a transfer payment from cities to localities. Bigger states, bigger transfer. Also, the federal funds are sourced from bigger states to the smaller states.
Thats one of the amazing things about the US. The wealth of the coasts ensured that the smaller states weren’t left behind.
As an example - city water vs Water wells & Septic tank/fields. Gravel roads without sidewalks, etc.
So it's not 100% evident that cities subsidize rural counties. Cities do provide the larger tax base for states, which probably subsidize more rural counties through incentives tied to certain rural activities, but making a blanket statement is probably not accurate.