This sounds like it has to do with timeshare exchanging (these Marriott resorts are timeshare resorts). Often a "guest room" or "hotel room" or "studio" at a timeshare resort is really designed for 2 adults, plus up to 2 children. They prefer not to suggest these are suitable for 4 people because so many timeshare guests complain when a unit is cramped for two adult couples.
So in the timeshare industry, they call the occupancy of these kinds of units "4/2," meaning they may sleep up to 4 people maximum but only 2 privately at the rate of 2 per room. When they sell these units as rentals, they often will go with the lower occupancy as the suggested occupancy. In this case, they are calling the room a "sleeps 2" to avoid complaints later. Disney does the same thing. They rent out the rooms of their sold-out timeshares this way... a 2BR at OKW that can technically sleep up to 8 maximum/6 privately is rented as a "sleeps 6," following this industry standard. Yet, they will not oppose up to 8 people registering and they will supply towels, bed linens and dinnerware for 8 people.
FWIW, though it will probably contain a mini-fridge, microwave, bar sink & coffee maker, it may say it has "no kitchen" rather than "partial kitchen." Timeshare exchangers are spoiled by full kitchens and expect more whenever the word kitchen is used.
This is a long way of saying that if you are satisfied with a nice offsite hotel room for your family trip (rather than a suite), you will love staying in a studio or guest room at the Marriott Grande Vista! It's a beautiful resort! Call the resort to verify all this, if you'd like.
