It can be a big time-waster, though.
I hate Facebook. I only have an account so I can communicate with my improv group. And I refuse to have it installed on my phone. I only access it through the web browser, and I have a plugin installed that blocks people's timeline updates. If it wasn't for my improv group, I wouldn't have a FB account at all.
I was using Twitter for a while for people I knew on Medium, but I've stopped now. I don't even bother logging in anymore. I realised I was just wasting time.
And oh my giddy aunt, the narcissism is sky high somtimes. It almost causes me to vomit in my mouth.