This is the closest we get to the economic theory of "Perfect Competition," which is a beautiful ideology of market efficiency, but tends to fall apart when we introduce human foibles, such as a question have power, or dominate, or amass wealth by sabotaging competitors.

That kind of stuff happens all the time in state regulated capitalism, and it is usually helped along by the state. (Corporations lobby government to pass laws and regulations that will harm their competitors or keep startups from entering the market; government passes a law that benefits a certain industry by requiring consumers to buy its product; government protects "intellectual property" on drugs and medical devices, creating monopolies in the healthcare market; etc.) So I'm not sure how getting rid of the state would increase the occurrences of this type of thing. If anything, I believe that in the absence of government, capitalism would suffer from far less abuse by the dishonest and power hungry.