I don't understand people who have like a thousand of friends on Facebook, and most of the time they just chat with 1% of them. I call them attention whores by default.
I struggle to keep the number as low as possible. I even have people I know from the university who tried to add me and I have pending requests from them. I don't want to add them but I don't want to refuse either, just in case. That's also the case with my cousin I don't really like too much and ex-friends I don't hang out with anymore, but who want to add me.
I hate the idea that someone that you recognize, but who wouldn't even say "hi" in real world would want to add you.
Or those "hey, I saw you 2 weeks ago on a conference/party/friend's house, I recognize your face but didn't feel like making an effort to socialize, I won't socialize with you after adding you to make sure we remain strangers and if you try to send me a message I will think that you're weird and you will not get an answer but I will add you regardless tee-hee" people. What's the purpose?
I have a few people I like from here though.