You can have minibuses where you can get on/off anywhere along the designated route. Farm these out to private operators (regulated, of course), and you will have lots of cheap point to point public transport. It requires a city to be dense, though. http://en.wikipedia.org/wiki/Public_light_bus#Pros_and_cons_...
Cars provide a circuit model. You go from point to point over a single dedicated "channel".
Any kind and combination of public transport does not do that. It is a packet model and you, the human, are the packet. You must change modes of transport and hope that they sync up, aren't running early or late, fit your schedule and so on.
Except in the cases where point-to-point travel takes substantially longer (very dense urban cores), I think most people will always prefer cars.
(Yes, I know the analogy is imperfect because the car can be seen as a packet blah blah blah. But cars are not sentient. Humans are and it is humans who decide what mode of transport to use.)
But, as opposed to real computer networks, packet transportation is much more energy efficient. Sending twenty people to the same destination in one `packet' uses much less fuel than having those people travel in twenty separated `circuits'.
As a society we seem to have mostly established the abstraction that energy is free and unlimited. From the recent explosion of amount of things humanity does we can see clearly how practically free energy is a desired state. However, we're not there yet. Until we really get there, forgetting that this is only a leaky abstraction is dangerous, as the leaks have deadly consequences.
I realise that on certain metrics public transport is better.
None of that matters. Who decides which transport to use? Humans. What measurement do they use? It's clearly not litres of diesel per passenger-kilometre.
"Humanity" is pretty good at economising scarce resources. But people are pretty clearly prepared to pay enormous costs (fuel, parking space, commute time) to have a private car. Arguing with revealed preferences doesn't change them.
Except that most of those costs (and lets include pollution) are externalities borne by other people, not by the actual car drivers. If people would have to pay the real cost for cars, things might look different.
If the city is dense enough, there will be minibuses crossing many point to points routes and you'll more likely to be able to travel point to point without changing mode of transport. Of course, it isn't guaranteed.
