He noted that it was not just a money-making scheme on the part of the publisher, trying to sell a new game to existing players.

There are four plants which cannot be sold to other players.

Most casinos employ chip runners, who sell chips to players.

Since drops are random and only players can sell to other players, the economy is still self-contained.

Creating user-controlled shops with which to sell items to other players.

The items created can be used by the player or sold to shops and other players.

He succeeded in playing online games and selling his game points to other players.

For much of that life, he has gotten into automobiles and airplanes to sell universities to players.

Selling products to other players and "the people" controlled by the game, the player earns money that can be used for the development of the company.

Frequently, power-leveled characters are sold to players for real-world money.