keeveek: Releasing free games just because they are free doesn't have much sense.
No, but releasing them to increase site traffic makes sense.
I have talked people over to try out both GOG and DotEmu (and even Steam, unfortunately...) with free games. Later, those same people have actually bought games from GOG and DotEmu (and even Steam, unfortunately...).
Even myself included actually, I first grabbed TeenAgent for free, and then later started to buy games - and now I have almost 300 titles on my GOG shelf (although only two for full price, but still).
(Have never bought from Steam, fortunately... :-)
So it makes sense to give something free and cash in later.
It doesn't always work that way though. I got a can of free Coca-Cola in Italy this summer as they were promoting it. I still buy Pepsi, if available.