No, bell-cot's point is that they are the same company that gets the profits from the payload. It's vertical integration (pun accidental, but not avoided). That gives them a massive financial advantage as a launch company. It makes it hard for anyone else to compete with them - if they have the capacity to handle all other customers' launches as well as their own.

Internet satellites... that does look like a monopoly, or at least effectively one.

Companies spin off parts of their process into separate companies all the time. Auto and airframe companies are notable examples. If it was more profitable to do these in house, they would.