You and I know that it'd be dumb for non-simmers/casual racers to just jump
into sim mode expecting to race, but they don't know that. Think Gran
Turismo fan that thinks driving there is a true sim.... or the guy that
wrote that PC Game World review of RBR. Show people a simulation mode, and
that's what they'll probably go for. Sure, they want to have immediate
racing fun, but they also want the satisfaction of not settling for anything
less than "real." It's silly, I know. If there's no choice though, they're
less likely to care if the physics are dumbed down a bit.
Just think of it this way... have you ever played GT with the "simulation"
tires? They're more demanding than the other tires and require more
attention to one's inputs. For argument's sake, let's say they definitively
are more representative of real life. I'm guessing most players didn't
switch to those once they discovered them, and though we'll never know, I
don't think GT would've done as well if that was the default tire.
Alan