You are confusing content with the delivery system. The fact that CDs are a bunch of numbers is trivial. A CD, tape, book, or DVD is just a delivery system for the content. The creation of a song, book, movie or any other art begins long before it is stamped on some media to be sold. For most artists there are years of effort involved in mastering their field and creating the content. Just because that content can be translated into a number does not in any way mean that you, or anyone else, has a right to that content for free against the artists wishes.
You are confusing content with the delivery system. The fact that CDs are a bunch of numbers is trivial. A CD, tape, book, or DVD is just a delivery system for the content. The creation of a song, book, movie or any other art begins long before it is stamped on some media to be sold. For most artists there are years of effort involved in mastering their field and creating the content. Just because that content can be translated into a number does not in any way mean that you, or anyone else, has a right to that content for free against the artists wishes.