I dunno, but it might be because everyone expects you to be on Facebook and check it on regular intervals, and thus uses it as the one and only medium of communication, thus escluding those who actually doesn't have it or check it on regular intervals. Then, the "OMG, I'm teh originalz" kicks in and causes people who aren't already connected to stubbornly refuse it, just because that separates them from the mainstream. (It might also be because Facebook claim everything you post on it as theirs and can use it for whatever purpose they like without your approval.)
There is a reason to why I titulated the refusing parts of my brain "stubidly stubborn and excentric", while the accepting ones became the "social and progressive": namely that Facebook is a lot more useful than evil.
Never happened to me, and go...odness am I happy for that. Driving is panicky enough for me without having to dream about it.
...
Okay, it's not as bad as it used to be. I'm a lot calmer behind the wheel now than when I began taking driving lessons.