The OP is actually right... if you think of all the stuff you are "doing" as a Sith it is very very mature stuff, pretty brutal. Much more than any other teen games, its stories and actions you take would pretty much be enough to give you an M rating on any other game.
I just wish there was dismemberment, i hate whacking things with my lightsaber and NOTHING ever happens except the fall over dead. For a game to let you kill someones son, kill an adulterer, slaughter innocent civilians for no real reason... to draw the line at cutting people up seems a little weird.
It is a mature game, that gets away with a Teen rating because its Star Wars... and no Star Wars movie has been R, only one was PG-13.
Not like I care about any of this, but reading the OP post got me thinking, and he's onto something.