You're title calls guild Wars 2 a free game. It's not a free game, it has a free to play option with heavy restrictions, which do not allow you to experience the full game or even experience the game as it was intended to be experienced.
Additionally, according to ArenaNet themselves, the game is Buy to Play. with a Free option that encourages you to buy the full game.
http://www.pcgamer.com/guild-wars-2-...e-is-now-free/
As quoted from the article, which quotes Mike O'Brien President and co-founder of ArenaNet:
None of this impacts my opinion of the game though, which I find to be very fun and entertaining if only because it's a little different in it's approach to leveling and story telling with no strict on rails questing and more exploration style game play.Guild Wars 2 is now free. You can download and play it right now, for nothing. But rather than a full free-to-play transition, ArenaNet is instead changing what you pay for. The core game is free; the upcoming expansion—Heart of Thorns—is not.
"As we start to release expansions, it raises the question: in a buy-to-play business model, what exactly do we want you to buy in order to play?" ArenaNet president Mike O'Brien tells PC Gamer. "We've seen different games go in different directions. Sometimes it gets pretty complicated. Sometimes you have to buy the base game and then every single expansion so that you can get the latest stuff and play with your friends."
Instead, ArenaNet wants to make things simpler. "We hold ourselves to the very highest standards of buy to play," says O'Brien. "You just have to buy one thing." For the studio, that means making the original thing free.
The above information is really just contesting the OP's claim that the game is free.