I read about this service as the ultimate example of marketing that aims to constantly jack up people's concept of what it is to "have everything you really need". Hence making us endlessly dissatisfied with life and desiring more stuff. In a book called Affluenza. At the linked site you can download the first chapter where the author points out:
Ten years ago the gold credit card was a mark of distinction, a sign that you had made it—or at least that was the message the credit card companies put out. But too many people began to qualify for the gold card and its symbolic value became diluted. So the credit card companies invented the platinum card, designed to be accessible only to those at the very top of the pile.
Determined to stay ahead of the game, American Express has now introduced a black credit card known as the Centurion.