Investopedia.com: Economies of scale is the cost advantage that arises with increased output of a product. Economies of scale arise because of the inverse relationship between the quantity produced and per-unit fixed costs; i.e. the greater the quantity of a good produced, the lower the per-unit fixed costbecause these costs are spread out over a larger number of goods.
Yes, and the scale gets even better if you can dump (social and environmental) costs on the public (negative externalities etc)
See also Minimum Efficient Scale