Once upon a time, the music industry made its money off of sales of sheet music, then it was sales of recorded music, and if it isn't already there it will be making money off of merchandising.
You've got it backward Jacob:
They take cute child stars from the Disney channel who aren't musicians, hire professional songwriters to write ring-tone approved hits to satisfy 12yo girls, and then promote the sh**t out of the song by having it featured on commercials, on MTV, on the radio. The stars appear on billboards, they're guest stars on TV programs, TMZ and Access Hollywood start discussing them.
The licensed products, commercial endorsements, and guest star appearances of its featured are where the music industry can make its money these days as 99¢ iTune singles ain't gonna make them a lot of money. They no longer need or want moody temperamental artistes who take three or more years to make an album so they can get it just right. (Besides, the album is essentially a dead art form right now.)