Are you referring to online games or all games in general? For online, it should be the choice of the creator(s).
For the games you got to the store and buy they should not be free, in fact, those who pirate those games should be hit with a very heavy fine, as pirating them is in violation of international copyright law. Think of it this way, the company sells the game at a price they choose, they must support the graphic designers, various programmers, managers, administrative assistants as well as rent, or the cost of the building, various utilities, computer maitenance and many more things. If all games were free, there would be no games with dazzling gameplay and graphics ((not that my computer will run them

))... Understand?