In fact you can define a lot about the setting of a game only through it's mechanics... this is why for example, I always say that D&D isn't so much a representation of feudal europe with titles and personal vassallage but rather represents a monetized society with the implication of trade and a commercial class... otherwise, it would not make sense that you can just walk to a shop and buy anything that the game offers. In a feudal or ancient setting, there would be almost no coinage to talk about, rewards should be in-kind (land, tribute) or more often, as patronage relationships (you are rewarded with a place within feudal society as a routine or vassal).
IN ANY CASE I would like to talk about that later when I'm not busy, but some games abstract these things so much you really cannot make the same implications.
