There are several locations to grab these and other fresh items. As @SteveH mentioned there is Fuel on the lobby level (3rd Floor) at the Dolphin. There is also Picabu on the Dolphin lower level (Ground Floor). Fuel is open 6 AM - 11 PM (Sunday - Thursday) and 10 PM on Friday - Saturday.I asked before about buying milk alternatives in the hotel - do they also sell fruit - bananas, apples, etc)?
There is also the Screen Door General Store over on the Boardwalk ( 8:30 AM - 11 PM ). The Screen Door has a variety of Breakfast items (Cut Fruit, Blueberries, Strawberries, and whole fruit). Bread / Muffins / Bagels, and Peanut Butter and last but not least Nutella.
Dave