If you bump a car off track then you deserve a penalty. In real life, the only way to avoid it is if the stewards felt it was clearly an accident, but the game has no way of distinguishing between accident and purpose. This is why you get a penalty. In most cases, in real life a penalty would be awarded for it, so if you don't like it, don't set it on realistic.
I have my settings on realistic and don't have any problems.
You misunderstood my post. I was not saying that I didn't like how the game is on realistic, I do. What I was saying is that I have not become a better and/or cleaner driver against the AI since playing on realistic.