I was watching a Browns game the other day and one of the players got a penalty for making a rude gesture. In the NFL, safety equipment and rules almost prevent players from hurting each other, and they definitely proscribe them from expressing themselves. They're isolated. (Unsportsmanlike conduct, my ass. Sports is an emotional activity. If I were down on that field, I'd be swearing the air blue. Until I got a bone broken.)
Your commute to work in a car: ditto. We're in boxes, isolated, held apart by hardware and laws. It's more than a little dehumanizing. I find myself stereotyping and disrespecting my fellow drivers in ways I never would face-to-face. The escalation of safety equipment in modern cars makes you feel invulnerable - my 2004 economy car has eight airbags.
Exception 1: the experience of driving a small convertible. You cannot help but be in touch with your surroundings. A few months ago my wife bought a Miata, and driving it home from Michigan to Cleveland was a revelation. The roar of a semi mere feet from a 2500-lb car is unforgettable. To be honest, it made me feel alive.
Exception 2: the Dutch experiment with removing all signs and markings from the roads of a town. How would you feel about driving around without the safety net of speed limit signs and police cruisers to keep other drivers from endangering you? It turns out that what happened in Holland was that drivers signaled their intentions, made eye contact, and generally watched out for each other and for pedestrians. They negotiated their own rights of way. Nobody got penalties for making rude gestures; there was no system to rebel against. Everybody wants to get where they're going safely, and they made it happen.
(Bonus points: what conclusion am I trying to get you to draw by not telling you the "moral of the story" in this post?)