ydobemos: Of course it does (or can). If it involved a product that people don't want then it wouldn't work.
Crassmaster: No, it isn't. Releasing a game that people want is called...releasing a game that people want. Whether you charge for it or not, it isn't an anti-competitive practice. It's a game release. Period.
There is NOTHING preventing other companies from doing the same, and NOTHING preventing them doing so for free.
Releasing a product that people want and engaging in anti-competitive conduct are not mutually exclusive. Anti-competitive conduct general involves a product that people want, the conduct would be ineffective otherwise.
For example, in Australia, the Competition and Consumer Act provides that a corporation that has a substantial degree of power in a market shall not take advantage of that power in that or any other market for the purpose of eliminating or substantially damaging a competitor of the corporation or of a body corporate that is related to the corporation in that or any other market.
I am not suggesting Valve is engaging in anti-competitive conduct, but, it could certainly be argued (and often is in other contexts) that a company providing a product for free (or less than the cost of producing that product) is in breach of this section (or at least the previous equivalent section in the Trade Practices Act). Obviously it would depend on establishing certain other facts, but it is at least arguable. Selling something cheaply (or giving it away) with nothing more, however, wouldn't be a breach of this section.
My point is, anti-competitive conduct can be found to have occurred as a result of conduct which ordinary people may not realise is anti-competitive such as offering products for free (or at discounts) refusing to supply to certain people, supplying to certain people on the condition they purchase other products, etc, etc.