Why do I have to have a Facebook profile?

I tried to post a comment but I can't unless I log in using my Facebook info.  I'm not a big fan of Facebook, and I don't like how it has slowly taken over the internet.  On a more personal level, I'm tired of Facebook eroding my privacy.  I simply want to make a comment on IMDB.  Why should I have to worry about all my Facebook friends reading my comment (out of context, and out of nowhere).  Let's face it, I've never even MET most of my Facebook friends.  They are friends of friends (and often even further removed from that).  Many are musicians that I'm a fan of.  That doesn't mean I want these virtual strangers to know my opinion about some film or some actor's performance.  And if I wanted to discuss it with them I could actually use Facebook.  You know, the internet used to be a little harder to use, and it wasn't as slick or responsive.  But on the other hand it wasn't ruled by a dozen HUGE players who are now in a position to make the rules for everybody.  (I'm sorry this went off topic at the end but I'm very frustrated).