Yes I agree this is a BIG problem. I ran into it years ago in Canada where I was promised by a hotel MANAGER that a large purchase I was making in a hotel shop would earn points. Turns out that this was not correct - and in the process I also found out that some of the restaurants in the hotel were "independently" owned so charges would not earn points - something I would never has expected.

Isn't there some way each hotel could make this a bit more transparent?