After a certain level of destruction, maybe 2/3 left, she begins to wander a bit. A brand new one gets her full attention again. Keeping the residue in check seems to be my only complaint at this point. And getting enough new boxes. . . .
Don't go there any more, but might see if I can find similar items, or friends that go there. I wonder if egg cartons would be a thing? Possible salmonella, etc?