Gratuitous Tank Battles creator: free-to-play "doesn't ask you to value the game until you already feel you own it"

The concept of distributing a game for no cost, once the domain of Facebook app-clones and mobile platforms, has quickly become commonplace in PC gaming. We've all seen clear evidence of such a phenomena, from the lessened emphasis on subscription models in MMOs to the availability of quality multiplayer shooters like Tribes: Ascend from a single download. In a blog post , Positech Games head and Gratuitous Tank Battles creator Chris Harris says the psychology of free gaming boils down to letting players set their own sense of worth before asking for money.

"Free to play works because it doesn't ask you to value the game until you already feel you own it," he writes. "How much would you pay for Farmville to buy it outright? Maybe $5? But play the game for free for a month, build up your farm, invest it, and then hit a plateau in the game where you really need to buy coins to continue, and suddenly your game is worth a lot more than $5. You value the game you already own very highly, and so buying add-ons for it is just common sense. I suspect this is why DLC works so well and sells so well. You have already made a commitment to valuing the game by investing your time. Only a fool could try to rationalize not spending money on it now."

It's almost as if Harris stumbled upon the secret formula of free-to-play games: foster a sense of ownership to encourage microtransactions and DLC. Item-heavy games such as Team Fortress 2 and PlanetSide 2 let you try out a shiny weapon for a short period before taking it away, but that brief usage could boost the likelihood of a wallet getting pulled out simply because you determined your own measure of worth on the item you fleetingly "owned."

Let's hear your comments. Do you only drop dollars on free-to-play games after you've built up a sense of attachment to them, or are your buying habits more free-form?