Americans subsidize parking by imposing fees on developers who don't include "enough" of it, and by reserving large portions of cities' streets for car storage. Multi-billion dollar highways enable sprawl and cheaper commercial parking lots. Driving & parking personal vehicles is incredibly wasteful from a broad economic perspective (but it was the correct path -- a necessary evil in the absence of density to enable effective mass transit).
Even with the government subsidies, Uber is an economically competitive alternative to driving & parking personal vehicles. That's the amazing part. Public policy favors the incumbent behavior, yet "ride-sharing" has still been able to expose market inefficiencies. Imagine if we killed all the parking subsidies, or better yet: used economic incentives to discourage driving & parking personal vehicles, and encourage the behavior that had a lower total cost.
I believe the future of personal transportation is computer-driven computer-dispatched vehicles, a game Uber and Google are leading. We can't get there soon enough.