And Amex does have a black card, it's not a rumor (though there are many untrue rumors about it). I know a holder, who not coincidentally is how I know so much about comp programs and how casinos treat high rollers.
And I didnt suggest that casinos don't make money off the high rollers. But they definitely make a greater and more stable cashflow from masses of low rollers than handfuls of high rollers. A smaller scale example would be the high end dept store in your city, like a Saks or a Neimans--their avg purchase is probably in the high 3/low 4 figures while at the same time at least once or a few times a day a high roller spends 10k+ on clothing. Probably with their Black Card. XD
It is made of metal instead of plastic, and to his annoyance, does not always fit in machines that take credit cards because it is a little thicker and slightly larger.