Why are you changing the topic to rural areas? We’re discussing whether suburban living (defined as car dependent urban design rather than literal suburb) is subsidized by people living in the denser, transit dependent areas or vice versa. Farm subsidies and military bases and whatever other rural subsidies you had in mind aren’t relevant for this discussion and suburban (and low density urban) people work in the services you claim almost all wealth in the modern USA is generated from.
OK, It depends what you meant with suburban. If you mean the suburbs close to the big cities, sure they are part of the wealth generation. A large part of people living in those suburbs are using public transport to commute to work.
The issue with cars is that it is impossible to build enough roads. The more you build the more convenient it becomes so more people drive etc. And of course the other externality of carbon pollution.
