While this may be stricly true, perhaps the poster is looking for a reply with a little more imagination. F'Talk assists many with creative solutions to this sort of dilemma. The author could consider offering up a barter of his AA points, which he can't / chooses not to use, in exchange for Marriott points / a Marriott deal which he does want to use.

I for one regularly entertain this sort of agreement, and would be happy to exchange 1:1, where I could employ and value 75k AA more than 75k Marriott.

Let the bartering commence!