The problem is Rockstar knowingly left material in the game that was never meant to be accessed, full well knowing that the PC Community would find it.
It wasnt necessarily intentional that the code was left there to be found. Most likely the feature was evaluated and they decided to cut it from the game, so the coder does it the quickest and easiest way - by simply commenting it out.
It's often preferable to do this because there may be something elsewhere that depends on a subset of the unwanted feature's code. If say, the publisher says the game is good as gold except for this one feature, and they want it gold by Friday, the programmer takes the quick & easy route to remove it without requiring a whole new round of testing.
Of course it's plausable they deliberately left it there to be found, but given their previous attitude towards modifications has left rather a lot to be desired, that seems less likely than the above.
BTW I still mean to imply it was Rockstar's responsibility to fully remove the obviously offensive code, merely suggesting it's plausable they failed by error rather than intention.