What's the deal with cell phones?

This question is aimed at pre-cell phone generation jellies – what are your thoughts about why people on cell phones so often wear that defiant, I’m-so-much-more-important-than-you look? You see it in the grocery checkout line, in the car behind you, trying to dodge their Suburbans in parking lots … everywhere. What is it about cell phones that cause people to become so insensitive to others, to talk so loudly, and to share so much information in public? As it regularly does, the question occurred to today in a small restaurant as I was forced to endure a woman in the next booth droning on endless about her insensitive husband (pot calling kettle black) with someone whose voice on the other end I could actually hear, too! I know this is a lost cause, but … HELP!