I'm no expert on this, but I can think of important counterexamples, so I'm not sure this is true at all.
Counterexample #1 - New York. It seems that this name is pretty much synonymous with the city plus a bit of surrounding area, and the upstate regions are completely forgotten. In particular, the areas that have to host NYC's water supply get particularly hosed: their economies are significantly based on tourism and fishing, but the flow of the Upper Delaware is entirely governed by NYC needs, ignoring the fish. Further, the State has banned fracking, largely in order to guarantee the integrity of the reservoirs, and at the expense of the only opportunity that those living on the Marcellus Shale have to escape their rut.
Counterexample #2 - Austin, TX. Again relating to water, it seems that the city gets priority access to water (a scarce commodity in much of TX). Lake Travis and Lake Buchanan were sacrificed, emptying to something around 30% capacity (I forget the exact numbers) until our recent floods, so that Ladybird Lake (the center of the city) could be kept beautiful and full - and they're even talking about building a water park. So suburban and rural interests were subordinated to aesthetics in the city.
What might exist in Camden that doesn't exist elsewhere is that, at least as far as local government goes, Camden doesn't have the governing tensions that exist in other cities, with a rich "governing class" (read: white yuppies) doing all that they can to "protect themselves" from "the others". Like all cities, it gets thoroughly screwed by the State, but at least locally, has far less of an internal "us" and "them" than, say, Philadelphia (which lies just across the river, and has neighborhoods with similar problems to Camden, but less policymaking authority to address them).