I haven't gotten to the point where I actually have finished the game entirely, I'm still at the "Make money and save the peasants" stage.
I think the whole, Black and White, Good and Evil side of this game is meant to lay it out for younger players, I'm not saying its a kids game, its not, but pre-teens and teens play a game and they dont want to have to sit for an hour weighing the pro-s and con-s of a decision, they want to get in there and kill more Knobbs. Making the Good Vs Evil thing any more complicated kinda takes you out of the experience a little, its like you have to stop and contemplate your actions a lot more "Do I want to save these people or burn their village down, will there be massive consequences or will no one notice."
Those kinds of things are fine for the older players, late teens to twenties and older, we just go "Eh, I'll just burn the village, take the heat and play through again later." Not too many kids have the stamina to play through a game a bunch of times to try different out comes.
Games like KOTOR have a great balance, you can do something nasty and then do something good and get a perfect balance of the Good and Bad, Fable is meant to be more simple, its not a massive huge level after level game, I played through till the half way point in one afternoon, I would have finished it in a day if I didn't get distracted by other things lol.
Anyway, I think its just a bit of harmless fun and a good way to spend a lazy Sunday afternoon.