I have never used Facebook, so I can’t chime in in these threads to say “I quit Facebook because…”, since I’ve never used it. The reason? Even if we disregard the admittedly huge walled-garden and privacy issues, it just seems to be an extremely time-expensive and constantly distracting hobby, with not much to really recommend it.
I'm also part of those who never registered an account on facebook because it was obvious from the get-go what this was gonna be about.
There were only one major difference from the previous similar services namely the shift to having people carelessly use their actual names which is something that was unthinkable until then.
And a minor difference in the large use of tricks from the dark book of anti-patterns and dark patterns to get more and more unsuspecting people on board.
To be 100% honest I did use facebook for a little while as I was employed in the shady business of uncovering online users identities and tracking them in the real world. The emergence of facebook made my job a breeze at first, then before long made the whole job position entirely expendable, clients would simply use facebook themselves to conveniently find all the info they were after in one place.