I really like your answer. Both of the characters objectified their food. Like you said Noel was your typical persom buying meat at a supermarket and never thinking of the animal.

Adam is also guilty of this, I imagine a salad wouldnt solve his unease after this encounter. He now finds himself guilty of his original argument is it humane to eat plants, and how can we know?

I would say they have been confronted with the idea that there are no real morals. Being confronted by this cows being has awoken them to the bitter fact that life eats life and opened the door for them to question the rest of their morals.

Edit: you should definitely read the books if you get the time. Its funny but still manages to be super deep, as well as being a unique and interesting story.