You can't pick and choose.
With the word simulator, there is a lot of latitude for what can or may not be included in the simulation model.
Now, if you were going to complain about replicator, then you may have a case. GT is not a replicator.
Broaden the definition like that, and basically, any current racing game can make an equal case for being a 'simulator'..! Personally, I think refusing to put a working neutral and reverse in a car's gearbox ought to upset these so called 'purist' car manufacturers a whole lot more than merely allowing some kid (because that's primarily who want to do most of these ridiculous mods) to swap an engine into it or add a few racing decals...
And, until the 'gifting after duplicating' thing is stopped altogether (let's not forget, the same fix that will prevent hacking the game save will also be able to stop duping), GT5 IS a 'replicator'! You can magically turn one car into two. How 'sim' is that?!
Just revisited this old post and have to say, (Amusingly) to all of the "Hackers":
If PD/Sony has the ability to reach in and grab your data from your PS3, Then consicer that their computer gurus have a way to short circuit your PS3 and burn it up. Consider yourselves lucky they didn't, LOL!
Sorry, guys, just couldn't resist.