My bunnies have a carboard tube that was covered in hay, but is now mostly cardboard, but there's bits of hay left and they manage to rip the top layer of carboard off and get big chunks of hay all in one go.
Walter is quite funny though. He'll grab a bit of carboard and pull at it then the tunnel moves towards him, so he tries to run away with the end of the carboard still in his mouth, making the tunnel chase him more, making him run faster...
It's terrible when your food fights back! :lol: