I used to work in an office with a large car park in West London and loads of people would commute by car. Partly because of the antisocial hours, but partly because it was generally a lot cheaper and quicker for them than coming in by train. That's bonkers, IMHO. Now I'm in Central London and the traffic is especially bonkers at night and the pollution is off the scale. Some people still drive and pay the congestion charge, because there is access to a car park (not very well advertised), even though we're only 5 minutes from Oxford Circus. Some people drive to a station on the central line, park and take the tube. Again they say it's cheaper than peak time trains and a lot need to drive to a station any way. Getting people out of their cars is hard!