Much of the land we use for animals is not land that can be used for farming. And the animals eat a, lot of the products that would be considered waste otherwise (i.e. Wheat chaff).

But yes, I agree. However, this is not specific to animals. We live our lives with excess. A supermarket needs to be well stocked at all times with flawless products or everyone will complain. This requires an industry that over produces and throws a lot away. A complete waste of resources.