In the same way someone would control all the colors in a monopoly game, a government monopoly would when the government owns all the outlets to a particular good, service, etc. (and in result have no competitors)
In economics, a public monopoly or government monopoly is a form of coercive monopoly in which a state agency or a public company is the sole provider of a particular good or service. It is a type of artificial monopoly created by the State.
State regulation prohibits all competition by economic agents other than the State. This monopoly can be justified for strategic reasons in certain particular cases of natural monopoly; for example, the provision of drinking water. It differs from a tobacconist, because in this the State is not the provider, but grants the monopoly to an individual or to a private company in exchange for an entry into the treasury.
