Well, if there are hundreds of companies doing deliveries for Amazon, then isn't "doing deliveries for Amazon" it's own industry? If hundreds of companies don't

Well, if there are hundreds of companies doing deliveries for Amazon, then isn't "doing deliveries for Amazon" it's own industry? If hundreds of companies don't form an "industry", then I don't know what does. In the industry of "companies doing delivery for Amazon", Amazon has a dominant position. They can destroy any one company, or destroy the entire industry on a whim.