People easily come up with simplifying assumptions such as "I need a car anyway," or "I have a driver's license and a car already." And when discussing #PublicTransport, we're sure to hear someone falsely asserting "everyone has a car."
Let's instead take the opposite assumption, one that's much easier to prove: "not everyone can drive a car," so there must always be at last skeletal public transport. And then we can discuss not "is having public transport profitable", but "is extending public transport beyond the bare minimum beneficial."
@lanodan @mgorny Yes, people who "have a car anyway" only consider the marginal cost for each additional trip - and they are economically correct, unfortunately. But getting rid of those annual expensive repairs, monthly installments, and taxes is worth a thought.
In my city, 20% of households are car-less. The majority are probably not urbal idealists, but simply old, sick, and/or poor. This is more than most people would have guessed.