Did she see actual evidence that a cat lived there? Maybe they had a guinea pig running loose, or a bunny. Maybe it was a cat that was a fan of Michelle Obama. Just sayin'...
With the price of lettuce in the stores nowadays, WHO can possibly afford to feed fresh lettuce to a dog -- who, IF they happen to like it, can easily consume half a head of lettuc in one sitting.
I have an image of a pampered cat's dinner of Fancy Feast, or white albacore tuna 'presented' on a bed of lettuce, for garnish.