Much like the system proposed by SEPTA, the Massachusetts Bay Transportation Authority had a one-way rail fare system. For a year. It didn’t work, though, as riders caught on that they could take the train into Boston for free and find another way home at the end of the day.
That’s why the Delaware Valley Association of Rail Passengers wants SEPTA to test the system before fully implementing it.
PlanPhilly has the full report on why the MBTA discontinued the system in 1991, why its reconsidering it and whether large transit systems like SEPTA can logically operate the one-way fares.