These guys are men of principle (there's lot of those in Finland) and they might be so stubborn that they'll never join FB. I think FB is there for good. It's going to change over time for sure, but I don't see it ever going away. FB or something similar will be part of our lifes for a long time.
What FB has really brought to me is the different level of friendship and communication. There's lot of people who I follow and who I interact with, I would almost never talk otherwise. This is the aspect they might not ever really understand. I just see it a pity.
If I check from their perspective, I don't think they'll really miss anything, since they don't know what to miss. And I'm not saying that's wrong at all. That's just selection of life.
And don't get me wrong, some of these are really my best friends and really smart guys. It's just so funny that they see something like FB or Twitter so differently than I.
Everyone just needs to make their own mistakes, like Geraint Andersson said.