Pay-to-win
In some games, players who are willing to pay for special items or downloadable content may be able to gain an advantage over those playing for free who might otherwise need to spend time progressing in order to unlock said items. In general a game is considered pay-to-win when a player can gain any gameplay advantage over his non-paying peers. Such games are called "pay-to-win" by critics. Market research indicates that pay-to-win mechanics are considered much more acceptable by players in China than in Western countries, possibly because Chinese players are more habituated to recurring costs associated with gaming, such as gaming café fees.[36]
A common suggestion for avoiding pay-to-win is for payments to only be used to broaden the experience without affecting gameplay.[37] For example, games—such as Dota 2 and StarCraft II: Wings of Liberty—only allow the purchase of cosmetic items, meaning that a "free-to-play player" will be on the same level as a player who has spent money on the game. Others suggest finding a balance between a game that encourages players to pay for extra content that enhances the game without making the free version feel limited by comparison.[38] This theory is that players who do not pay for items would still increase awareness of it through word of mouth marketing, which ultimately benefits the game indirectly.
In response to concerns about players using payments to gain an advantage in the game, titles such as World of Tanks have explicitly committed to not giving paying players any advantages over their non-paying peers, while allowing the users buying the "gold" or "premium" ammo and expendables without paying the real money. However, features affecting gameplay and win rate, such as purchasing a 100% crew training level, a premium account, premium vehicles, and converting experience points to free experience points, remain available for the paying customers only.[39][40]