We're complex beings, and there is always more to learn. Caring is more important than "knowing." Are we interested, receptive, curious? The element of surprise can fuel a sense of newness and add excitement when we're open to it.
Many people would have us believe that going through life as though on a well-worn path can promote apathy, boredom and even anxiety. There are oodles of books urging us to find the new us and step out of our comfort zones.
What is this first name stuff and why does it bother me? I understand the whole "let's be friendly" movement. The problem comes when you recognize that giving one respect over another diminishes someone, and perhaps that's why we have a protocol called manners in the first place.
Clearly, these gut feelings are untrustworthy. Not only is familiarity a maladaptive guide to what's beneficial, it can lead to choices that actually exacerbate stress -- increasing the likelihood of more poor judgments.