"I am superior"

Every day on my commute to and from work I get to observe people's driving habits. One of the most puzzling (and annoying) is their practice of roaring past other cars on a busy two-lane highway who are driving at the speed limit when there is absolutely no significant advantage to be gained by it. At best they gain a very few seconds of time. They burn up gas and more importantly they drive in a reckless manner in order to gain the few seconds. Why do they do it? There is no logic whatsoever to support their driving that way. My only conclusion is that there is a subtle matter of pride that compels them to do it. "Because I passed that other person, I am superior to him."