For some stuff I don't care, some other makes me jealous and some other is actually cool to discover/learn (think of some new place to have lunch/dinner or some hobby you didn't know about your friend).
But in general I am with you, and I also feel like most people liking and commenting are playing the social game.
I am not very active in social networks, though...
~Why is that? Any extra resources on it not being trustworthy?~
Nevermind, I just read other comments below :)