Back when I had two cats this was never a problem because one cat would always eat the other cat's puke. Now that only my little girl is left, it's usually one of my socks that finds it now.

Random irrelevant fun fact about my cats: my boy cat weighed 18 pounds and my girl cat weighs 6, and I always saw huge poops and tiny poops in their litter box and naturally assumed that my big boy was responsible for the big poop. But after he died I was left with just the huge poops in the box. Quite a surprise.