More importantly, there is a big difference between personal locomotion and commanding a vehicle. For example, the difference between my walking pace and that of an Olympic champion sprinter is not THAT great. However, the difference between my freeway merge speed and that of my mom is an order of magnitude. Add in fixed and inflexible travel lanes, the ability to speed up and slow down consciously and unconsciously, traveling at speeds that will knowingly cause death in the event of a problem, etc. and you have a lot more variance with higher stakes to the participants.
I'm not saying it isn't a fascinating bit of trivia, but I think Tom Vanderbilt's book "Traffic" is apt to lead to more insight than this particular nugget of knowledge.