This is a paper bag from our local chip shop (hang on a minute, there's a Homer Simpson voice in my head going 'Mmmm, chips...'). Sorry. Anyway, can you see what's wrong with this picture? The fish has the knife and fork. The fish! It's just wrong. A fish can't eat fish and chips!
But weirdly, cannibal animals are quite common. You get barbecue aprons showing a happy pig frying sausages, or a jolly bull barbecuing a steak. The French advert below is a rather graphic variation. It did the rounds on blogs a while ago, and I think you can get it on T-shirts now.