75% of gamers have bought virtual goods

Is that because those 75% are farmvile players?

Ok in all honesty, many f2p games are intended as exactly that. Free to play and buy some online goods. I find that sometimes these f2p models are actually quite nice and can be worth spending money into. Other times I find f2p models evil and crippling the none f2p people. A good example was a mmorpg where you pay for a month of faster (2x) exp gain. Which is great and many do it, but the mmo was free otherwise. And you are not really crippled without the double xp.