It’s a passive way to engage with your friends.
Do you like watching TV? It’s like watching a TV show that stars your friends. Or better yet, it’s a Web comic that stars your friends. Why do you check on the Web comic every day? Well, to see what the characters are doing. Same reason to check Facebook every day - to see what your friends are doing.
I will say that IMHO the quality of your Facebook experience depends on the quality of your FB friends. I’ve got 173 friends. Probably 100 of them never post or interact. Then like 25 of them are related to me. The other 50 are people I’ve chosen to be a part of my Web comic. They’re all like-minded with me, they all have a similar sense of humor as me. Some watch the same TV shows, some like the same sports teams, some I hang out with offline, some just think I’m neat. My “Web comic” is totally suited for me.
On the other hand I have friends who either have family members that post shit that bum them (my friends) out, or they friended people who are rude and/or dramatic or downers. I have friends who can’t say things they’d like to say on FB because they have co-workers or relatives who’d freak out. Friends whose friends do nothing but post game shit to their news feed. Those people hate FB and can’t see how anyone could like it. That’s because the quality of their experience is dragged down by the quality of the characters in their comic.
As for putting your life out there…no one forces you to do or say anything. If you have something interesting to say, you say it. If you have a photo to share, you share it. If you like something your friend posts, you like it. You can comment on it. If you got nothing, stay mum.
It’s not like by joining Facebook suddenly the Internet becomes privy to the contents of your fridge and your DVR and knows your daily schedule.
And the old “well if I want to contact my friends I’ll CALL them” excuse well that’s comparing apples to oranges. I’d think you were a right asshole if you called me any time your kid’s team won a game, or you made something exotic for dinner or you liked an article you read. But if you just mention any of that stuff on Facebook I can scroll past it, or click “Like” or comment on it. We could even discuss it further, and maybe I could discuss it with your other friends. And now I know about it, and now 80 other people know about it, and we can all decide what to do with it, and no one had to talk to your boring ass on the phone. You see?
But still you don’t need to be on FB. And if your friends are lame, you might not enjoy Facebook.
All that advice is free, too.