Appa's stomach was growling. Those hairless monkeys, the humans, were leaving him alone finally. Luckily he was in a lush field with plentiful berry-filled bushes. The hairless monkeys also left their food unguarded. This was going to be a tough call. The grass looked so nice and fresh, the berries looked as thought they would melt in his mouth, but the human's food look like a sweet forbidden fruit.
Appa decided the only way to resolve this dilemma was to further examine his options. The grass was just the perfect shade of green. The berries were so ripe they looked like they would fall any day now. But, the human's food, it was what humans ate, therefore it must be good.
Just as the first humans could not resist the forbidden fruit, Appa could not resist the not so hidden human food.
"Appa!" Sokka yelled, catching a glimpse of the flying bison eating his food. "AANG! Control that monster!"