In most cases it's the city folks subsidizing the rural folks. It turns out that it costs a lot more money to build the roads, power lines, schools, etc than the small number of rural residents that benefit from them will ever pay in taxes [0]. And in the specific case of New York's MTA, revenue from subway fares has repeatedly been diverted to pay for things other than the subway [1].
Everybody benefits from farm access to markets. Rural roads are there for everybody. To say 'its more money per capita for rural folks' just means you're using a heatmap of population and putting it over infrastructure - shazam, it doesn't match!. But it says nothing about who's getting the utility out of the infrastructure.