But people always have control over a company, even if that company has a monopoly. They can simply not buy the company's product or service, or use an alternate product or service. It may not be as good as the one offered by the monopoly, but no company is forcing people to pay them for their goods and services. In fact, the only entity that is forcing people to pay them for the goods and services they provide is the government.
The very definition of monopoly is that there is no alternative. I can't just go to another company because they, for instance, do not have the people I'd like to connect with in their network.