What universe are you living in? Railroads were some of the most
subsidized transport systems in US history, arguably moreso than normal roads ever have been. In the 19th century railroads were basically subsidized by the Federal government per mile of track they laid, rather than connections, which lead to MASSIVE inefficiencies in rail layout and design, as well as massive amounts of cronyism between the Railroads and the Feds. Even to this day much of the rail system is subsidized and many of the tracks laid that are still in use were laid on the taxpayer dime. Sure they may have to pay for upkeep now, but the Federal government doesn't pay for upkeep on the normal roads either, that's all at state level.
. . . No, because roads and the need for publicly maintained road systems predate the invention of the automobile by MILLENIA. Building usable roads has been considered a basic part of government responsibility since AT LEAST the fucking ROMANS. The US Constitution, which predates the invention of the automobile by around 100 years, explicitly sets aside one of Congress' powers to be to: "To establish Post Offices and post Roads;". Further, automobiles are just an extension of horse, carts, and the like, all private forms of transportation that were widely used by individuals prior to the development of railroads and ones that utilized public roads, and were usually privately owned by individuals who lived outside of cities (which, as a reminder, prior to the industrial revolution, WAS THE MAJORITY OF PEOPLE).
The urban centrism of not owning a private means of transportation is something that ONLY appears once you have the industrial revolution and you start to see the majority of people living in urban areas where they can walk to work and have food shipped in via mass transit. The invention of the car and making it cheap so that even lower class people can afford one and the resulting exodus out of cities into suburbs is more a RETURN to pre-industrial standards of living, and the constant bemoaning of it by people is ridiculous. Living in cities is BAD for human health and wellbeing, humans need a degree of greenspace around them to BE HUMAN. We're not hive dwelling insects for goodness sake, and technologies that allow us to spread and have a degree of person living space and freedom should always be embraced and encouraged. Urban centrism is a soul rotting evil in humanity.