Originally Posted by
Antarius
Yes and no. They can change aspects of the program, but they cannot arbitrarily change everything. For example, they can make Platinum into Gold and add a new tier above Ambassador, effectively demoting everyone. Not much we can do about that.
You cannot, however, unilaterally change terms of a contract. If I book a suite, the hotel cannot just give me a closet and say, tough .... - we changed our rules. If I book a fully refundable fare, an airline cannot retroactively require me to pay a change fee. This is a case of the latter. SPG or Marriott T&C may say that they can do this, but courts do not share this opinion.
But antarius
1) SPGs rules stated clearly that if you cancel after cut-off date (= no-show) your credit card is canceled and points returned. And you could appeal Perhaps SPG did not always follow their rules - but apparently those were the rules in effect when OP made his reservation. The fact that he did not read them is his fault
2) Delta devalued its miles as have other programs. If you don't show up for your airline, they do not have to refund you
3) You cannot find one court case stating otherwise