It could be a sustainability thing: If you butcher an animal, you have X lbs of meat now. Maybe you don’t need all of that immediately just to survive. If you

It could be a sustainability thing: If you butcher an animal, you have X lbs of meat now. Maybe you don’t need all of that immediately just to survive. If you only need Y < X to feed yourself, you can sell the excess and buy a new animal plus food to fatten it up. This converts a onetime benefit (killing an animal you have now) into a sustainable way to provide for yourself.