For all the hubbub about calling them Role Playing games, there doesn't seem to be much thought given to diversifying what roles the player can take. Every time a new game comes out, one of the selling points is always how many classes you can choose from. Can you customize your own class if you want? And what attributes do you get to make them up with? Yet in most Role Playing games, be they party-based, free roaming, or massively multiplayer there is always a distinct line drawn dictating what you can and cannot be.
You always play the hero and while this can mean a great many things--a knight, a mage, an assassin, etc.--it is a restriction nonetheless. In a world assumedly filled with farmers, masons, blacksmiths, and other people all furnishing the hero, you are never allowed to actually be one of these people yourself.
The immediate question is why would you want to? If given the choice, why would anyone pick to be a farmer over an adventure seeking rogue who explores dungeons and slays trolls for a living? It seems like a brainless question, but really as games continue to progress and advance it's a bit silly to deny gamers such occupations when a good many of them might actually enjoy it.
As drab as farming may seem, when well done can be make a fun game. The various incarnations of Harvest Moon have more than proven that. As demonstrated by last year's Rune Factory, it is possible to couple things like crop tending and animal raising with more traditional fair like dungeon exploring. Imagine if you could be a farmer in Oblivion.
Or better yet imagine the possibilities that would arise by allowing players to choose such a class in an online RPG. The potential for a player-controlled economy would be broad and as long as developers found a way to make every aspect of the game fun, it would benefit everyone. Online gaming is already very widespread; how much more popular could it be with the added draw it might get if a game like World of Warcraft were to give less quest inclined players a place to play?
To say that every fan of RPGs would enjoy trading in their battle axe for a hoe would be foolish, but then again not every player wants to play as a knight, mage, or assassin. If people are willing to play a certain way, why deny them the right if you can give it to them?