It's evident that in your opinion, Bach and Mozart are better musicians, and Citizen Kane and Rashoman are better films. I happen to share that opinion. But you and I are just two people, and judgments about aesthetic merit are not the same as measures of value. The fact that lots of people pay money to hear Miley Cyrus and Justin Bieber means that their music has value to all those people, whether or not it meets your or my aesthetic criteria.