1) I can get anywhere I want with public transportation as it is right now. The problem is that it takes literally four to eight times more time (in my specific circumstances), and my time is far from free.
2) The notion that it's free is, frankly, dishonest and disingenuous. *Somebody* is paying for it, and that somebody is me, in one form or another. Just because the money is not coming directly from your wallet at that instant doesn't mean it's not happening.
3) It ignores subjective value. I often enjoy driving. I don't enjoy being crowded into a bus or tram / trolley. Trains aren't too bad from a comfort standpoint, but still not as fun as driving.