They would never have known. When you cook the goose, you get a nice meal but you never know about the golden eggs that never got laid as a result. Everyone thinks they did the right thing except for the goose.
Yeah, but almost always geese lay regular eggs. You cannot just never kill geese in the offchance one lays golden eggs. The maintenance costs get astronomical.
Agreed. I was responding to the question of whether the cook ever realizes the mistake. Of course he doesn't - particularly if it's a new cook or someone who thinks geese are fungible.