If the people who use public transport, like buses and subways, in cities had to pay for it fully, would there be any in the USA?
Probably not.
They put in a bus line at tremendous cost where I used to live. At the end of five years they deemed it a success when it reached the point of paying 50% of its operating costs. That was just fuel, general maintenance and drivers. Any infrastructure cost was picked up in toto by the city tax payers.
Often the buses were empty and it took two traffic lanes out of use during rush hour.
Also many of the passes were subsidized by the city so even the 50% was not real.