FB has already inferred your identity from the graph structure and by referrences to you in conversations by family and friends
This! People think it's just a "Facebook problem". It's not. Many services work in a similar way, FB just one of the high-profile ones. After the initial enthusiasm, at least tech-savvy folks think well before installing a new app and giving your real name (or even an e-mail address that you actually regularly use) to any company on the internet.
And why I delete my Reddit account and re-image my computer every few months. And why I use a VPN.
You don't have to outrun the bear, just the guy next to you.
You don't delete your HN account every few months it seems ;)
It's a better community and I say things in less controversial ways because of it.