I consider my pets, pets, but what got this guy in trouble was his intent. It wasn’t like he did this because he was hungry and didn’t have anything else to eat. He did so because he was a jerk trying to get back at his ex-girlfriend. Laws may vary from place, but this rabbit was a pet and most people don’t eat their pets.
His intent was to cause her pain. Her intent was to cause him pain via this prosecution. They are both jerks. Whatever his intent, it is only a property crime.