You don't do it because it's "cute," you do it because your dad/best friend/lover/whoever has a perfectly good steak lying there that s/he isn't eating and it would be shameful to let it go to waste. (Or because you're at a restaurant and everyone ordered something different, but it works at the dinner table too, because stir fry that's still in the pan is leftovers but stir fry on someone's plate ends up in the trash or the dog bowl if someone else doesn't take it.)