Is Facebook an unnecessary trend or a valuable tool in today's world?

[Baaaabaa]

I think people get too sucked into Facebook. However, after deleting mine, I can't help but wonder-is it actually a valuable tool?
I recently did some work with a media company and one of the first things they asked me was if I had Facebook (so I could "like" their page, if I wanted to). I said no, I didn't. But I wonder if it is something people actually expect of people in a professional way?
I'd rather a potential employer contacted me by phone or email, personally, but you see my point!
Or, on the other hand, is my being Facebook-less actually one of my "unique selling points"? Are people more likely to be intrigued as to my avoiding the social network circle?