I don't know where the prior poster got the information (it might even be that Marriott has a "marketing" description which doesn't match their actual T&C). However, for elite members (which is what I was referencing) at full-service properties (which is what I meant to be discussing) the actual Terms & Conditions are consistent with what I posted originally, as follows [I added the bold]:
The Ultimate Reservation Guarantee: To be eligible, your Marriott Rewards membership number and a valid credit card number must be part of your reservation. If unable to honor reservation, the hotel will pay for your accommodations that night at a nearby comparable hotel and compensate the member for the inconvenience. Compensation varies by lodging brand (see below):
At Marriott Hotels & Resorts; Renaissance Hotels & Resorts; Marriott Conference Centers; Marriott Vacation Club International; and Horizons by Marriott Vacation Club: Alternative accommodations, plus $200 and 2 free room certificates.