It's like how different people eat their Reese's Peanut Butter cups. In this clip, Bunya chews the tunnel from the inside.
I love is the way bunnies chew. They go at it like little motors, but partly side-to-side. You can see the slightly bemused and mischievous expression that inspired some cartoonist to make Bugs Bunny's tag line: "Nyaaaah, What's up, Doc?" That cartoonist must have seriously studied real rabbits before beginning to draw the character.
