Public transport is only more environmentally friendly if people actually use it. Out where my parents live it was not uncommon to see busses driving for miles with 0-2 passengers. The problem was that providing good enough public transport that you didn't need a car at all is basically impossible. And since everybody had a car, the number of people that wanted to spend 60+ minutes taking a buss that went 3-4 times a day into town, instead of driving 30 minutes, was basically zero. They eventually cancelled the bus line since it was just too expensive and inefficient to run. The alternative of trying to provide a truly useful public transport service (say 2 buss lines running every 30 mintues) would have been extremely expensive and would have meant even more empty busses.