Is there a point to Facebook Ads?

The ad Buffalo Wild Wings is always up on my wall, Bieber Backstage, and coursesmart.com a site for college text books. I find these pointless but I think in some ways they could possibly be helpful or effective. It just depends, for example i would like to visit coursesmart.com but I have absolutely no desire to listen or watch anything to do with Justin Bieber. The ad for buffalo wild wings are funny because it is a picture of a hot wing and labeled 'buffalo wild wings'. I feel like these ads intentions were to make us more socially tied to one another but failed because noone knows they're advertising legitimate things.