My guess is that it's related to Madonna's continuing ability to outgro$$ everyone else in the entertainment industry on concert ticket sales, which represents huge attendance, huge interest, and huge television viewing numbers, which translates into good ratings, and translates further into ad dollars and big profits for the show producers. Her last world tour grossed over $200m and she ranked #1. Bruce Springsteen came in #2 at $170m. Hard to believe Madonna grossed more than Bruce but she did...More than U2, Celine, Bieber, & Taylor Swift.
