Bad for cats' respiratory systems. The reason for the discontinuation of the Pippin Cat Litter, was caused by the fact that it was not good for the cat's respiratory system. Cat litter is used by owners to bury feces and urine for their cats, and is highly absorbent. It is used in conjunction with a litter box (or cat litter box), where the appropriate amount of litter is poured into the litter box, and trained cats will walk into the litter box when they need to defecate on top of it.