A shill is a person employed by a casino to play at a table so that it looks busy. Empty tables tend to stay empty, so a few shills playing with the house’s money can draw real players in, especially in games such as baccarat or poker. Outside casinos, the word is used for anyone who promotes something while pretending to be independent, much like a stooge.
Because shills play with house money, they cannot cash out the chips they use, and in house-banked games they are not competing with other players for their stakes. Proposition players in some poker rooms, who are paid a salary but play with their own money, are a related role. For online operators, the lesson is transparency: bots or staff presented as genuine players are not acceptable, and peer-to-peer games need fair-play policies that rule them out.