It's FREE! Need I say more? Trying a free to play game only costs you the time to download and play it. There's no risk, there's no investment. You can download it, jump in, and see if it interests you. With the profound lack of demos these days this is a god send. Plus the shier quality of many Free to Play games has gone significantly up within the last few years. If you told me in 2009 that games like Hawken, Warframe, and Star Conflict, would one day be free to play games, I wouldn't have believed you. I would have told you that those games look to high quality to be Free to Play. That a Free to Play game is something like League Legends.
Of course that's not true anymore, Free to Play have evolved just like every other part of the gaming industry. They have evolved for the better, and now we are starting to see them make they're way onto consoles not just the PC. I would now dare to say that many Free to Play games rival the quality of 15 to 25 dollar titles.
Now with all things there are problems with Free to Play games. The classic argument is pay to win. Pay to win exists, it's just doesn't apply as often as most people think it does. It does apply when you have a strictly competitive game that is unbalanced due micro transactions and other various purchases. It doesn't apply when you have a cooperative game where all the players trying to achieve the same goal. Yes, they may have a better armor set or equipment than you do but if anything that helps not hiders you. They decided to drop 30 dollars on this game, that is completely fair. They spent money on this game, you didn't. Your still playing for free, they aren't. They've now invested more then they're time into this title. They've shown the company that they are willing to pay for the title and so yes, if they have a more fun experience, they deserve to do so.
The major problem with these purchases, is the pricing. In the Free to Play game Marvel Heroes you can pay up 250 dollars to access all the content within said game. That is outrageous and unrealistic. In a perfect world you'd pay 60 dollars for full access, like most retail games, of course that never happens. Warframe is a great Free to Play cooperative experience but the starter bundle is a staggering 40 dollars. I can't speak for most people, but I personally would spend a lot more money on Free to Play titles if they're pricing was more appropriate.
With all that being said, I'm still astounded that some people can complain about a free thing. Or write them off as something illegitimate and not worth the time. I encourage anyone who hasn't tried any recently released Free to Play games to give them a try.