I don't know if CR and BC are different, but at Poly there was a store that sold alcohol, snacks, milk, fruits, frozen meals, ice cream etc. in the great ceremonial house, they had bananas and apples. At captain cooks there was also a few fresh veggie/fruit options to purchase individually.
Maybe
@Lisa F knows of the stores at the other resorts are just as convenient to the rooms, and sell similar items.
I haven't stayed at BC/YC in the past 6 years, and never paid attention to the store or qs then.