Just a simple idea that came to my mind to make shelves a bit more interesting. So far their uses are to remove beauty penalty and outdoors deterioration. My idea is, it could be useful if food that's stored in a shelf couldn't be eaten by animals. It makes sense, since you are raising your food so your dogs won't eat anything lying on the floor, and could be useful for instance to store packaged meals for caravans relatively closer to the animal's beds without fear that they'll use them for breakfast. It could also protect chicken eggs from being eaten by other animals, now that I think about it...