We are DVC members so we automatically have at least a mini-fridge at any DVC accomodation. However...do you "need" one? It depends on what you intend to bring home. If you will bring a boxed piece of cake, I'd say no. If you plan to bring a part of a steak, it should be refrigerated. However, I'm not sure it is worth the cost to rent the fridge.
Think about sharing meals so as not to have so many leftovers...or just saying that you've had enough and not boxing things that need the fridge.