With no clear single source attached to this clip, its appeal online comes from the instantly recognisable sound of a grumpy cat eating noisily. Short pet and eating sounds travel well because they need no explanation, so creators reuse this one as a quick reaction for hunger, greed and food envy. It fits comedy edits, animal compilations and chat stickers where a loud, messy bite says more than a caption. Because the nom nom rhythm is easy to recognise and repeat, it keeps working as a punchline whenever food, pets or a very determined eater takes over a scene.