Where did you see it? I wouldn't doubt it though--many are offering at least an optional all-inclusive program since it is so much in demand.
I would love to stay at one of the Marriotts, but the prices are always too high, it would be great if they offered an all-inclusive!
The Marriott website says as much...a promotional package? http://www.paradisebymarriott.com/packages/offer.aspx?id=1