People who had their locker beside yours in high-school are not 'long lost friends'
Yes, they pretty much are, almost by definition, since they are/were friends who you lost touch with a long time ago.
they don't need to see photos of your cars and kids nor need they to know where you live.
Need? No, but maybe they want to. I know that I have really enjoyed seeing photos of friends from high school, their kids, whatever, and have had some fun exchanges catching up with people I hadn't spoken to in years. In my case, I grew up on military bases, so it was particularly easy to lose track of people, especially since this was pre-Internet. Just because circumstances caused me to lose touch with someone doesn't mean they should be permanently erased from my life. Just because I don't call someone on the phone every Sunday doesn't mean that I don't enjoy a quick browse of their photos, updates, whatever they post.
Listen, if you don't want to read or post to Facebook, fine. But you're being an arrogant ass to tell others they shouldn't. Not every interaction with people has to rise to the level of a discussion over the validity of Keynesian vs. Hayekian economics. Maybe I just want to see a cute pic of an old friend playing with his daughter from time to time.