The hay cube box is our attempt to keep the hay dust to one general area. Of course, the bunnies often grab a choice cube (do not ask me their criteria) and run off with it to chew someplace else (and do not ask me why that someplace else is preferred - I don't know those criteria either).
Although Ethel was in the hay cube box, her attention was not on the hay cubes, but on the box.
I am not sure if she was playing the piano, shadow boxing or "peeling" the box to get to the good parts (again, don't ask me...).