Minnow, I wonder if it is the sound or the fact that she can destroy the paper? Kind of like how a young child likes to cut up paper just to cut up paper.
My sister's cat has a thing for walnuts. They used to have a bowl of mixed nuts of their coffee table. Their cat would pick out the walnuts, and only the walnuts, then play with them. Maybe she liked the little rattling sound. Each day, they'd find them all over the house. They'd be under the stove, in the dog's water bowl, under the couch. Who needs toys?
Nakhash, I have heard that cat's have a fascinating with water and the toilet flushing. I guess it's a good thing they don't have hands and can't work the flusher themselves.