Mustard, you have made some articulate and well argued posts for the car - some of which are irrefutable. Thesweetcheat is a bit of a hero in my book, constantly working out his bus and train routes, always willing to enter into good natured dialogue on a subject he clearly feels passionate about. You summed it up, however, with these words "The car is simply too comfortable, cheap and convenient to be easily displaced."
I haven't really got anything to add without the risk of tailing off into gloom and/or grumpiness. For inspiration I recommend Robert MacFarlane's "The Old Ways - a journey on foot" also his "The Wild Places" - reading about ancient routes across and around the British Isles is inspiring and I suspect some (who are fit enough) would be tempted to walk the same 'old ways' at least some of the time.
Which would be a step in the right direction.