Last week Erin at "The Zoo" called her bunnies organic garbage disposals. Mario also does his part to keep the landfills clear. Here he is nomming down on some grape stems:
I ravage you grape stem!
Other examples of "table scraps" Mario also gets are peels, lettuce butts, and the outer layers of the cabbage. He seems to like the grape stem almost as much as the actual grapes. Almost.