If I as a producer need to manufacture 100g of something, whether it’s all consumed or not I still need pay to produce all 100g, what benefit is there in paying to produce something that doesn’t get consumed?
Let's say all consumers collectively eat X kg of ketchup per month. If 10% gets left on the bottle walls, they are buying 10% more, thus ~10% more profit for producers.
It works the same way we are using much more laundry detergent and toothpaste than necessary.
