Facebook Movies?

Does anyone even buy CDs or DVDs these days? Everything can be done online.  In order to boost sales and increases revenues, Warner Bros has said they will begin renting movies through Facebook.  I guess they realize everyone has a serious addiction to the social networking site so this would make perfect sense.  One of the first movies they will release will be hit, The Dark Knight.  How it works is if you "like" a movie on Facebook you can pay to watch it online with 30 Facebook Credits which is equivalent to $3.  For doing this, Facebook will get 30%.  This $3 price seems pricey compared to RedBox DVDs which you can rent for just a buck, however Apple's iTunes movie store charges $3 as well.