According to them it is structured differently. If they are part of the Amex programs they are part of them all the time, they don't get excluded because they drop their price, but it sounds like Amex's program is shown to the hotels they invite to join, and the deliverables are all comped out the same, so not individually negotiated with each property. Kind of like, here is our program, what you are required to offer guests through it, what we will offer you, so either you accept and join or you don't.

No negotiating how much to pay for breakfast, or whatever it may be. Not that that it's a fixed amount of $20 per person for breakfast, but it sounds like their program is hotels in Price range 1 get this much per person for breakfast, Price range 2 pays this, and 3 pays another amount.