Because what you're primarily saving with public transport is not the cost of the vehicles themselves, but all the infrastructure needed if people who would oth

Because what you're primarily saving with public transport is not the cost of the vehicles themselves, but all the infrastructure needed if people who would otherwise take the bus all own cars. Sure, if the 50 people on the bus all buy used beaters you'll probably come out ahead, but once you start thinking about the real cost of the land in big cities needed to park those 50 cars it gets expensive real fast, and that's before factoring in extra load on the road system and other externalities.