Unless you're using Zip Car or some such service, you probably own your own vehicle (or the bank does). When you get into your car, you are in your own private space. Your things are around you, your music or radio station is playing. It's like a little piece of home on wheels.
Meanwhile, your vehicle is on a public road. Public means that it is a shared space for all to use. The idea of a public space carries very specific social meaning to us. There are certain behaviors that are simply unacceptable when one is in a public space.
What makes driving unique is the private bubble containing us while we operate within a public space. I have observed that many people exhibit private behavior patterns when they drive. Behaviors which I have a hard time imagining they would exhibit if they weren't in a car. For example, when was the last time you walked up to the front of a long line (queue for you Brits) and just stepped in front of the first person? Unless you are a bona fide sociopath, the answer is likely "never." Yet, how often do you see someone zooming past cars piled up in the only remaining lane in front of a lane merge during heavy traffic?
Somehow, the private space of the vehicle causes many people to forget their manners. The great irony is that the line-cutters anger others into doing the same. The result is a pile-up at the choke point that would not even be there if everyone got into the only open lane before traffic began to constrict.
We see antisocial behavior in cars all the time. People double park and then go to a meeting or to their offices or to the mall and behave like perfectly normal human beings who understand the rules of public behavior. Maybe we need a new public relations campaign. The slogan could be:
DRIVING IS A PUBLIC ACTIVITY. ACT LIKE IT IS!