Crash doesn't do that, and that's largely the reason for its glowing reception, in addition to its natural cachet for tackling a "tough" subject.
But the dialog for the film is clumsy and overdone, implying that racism abounds only in overt forms. Quiet racism is just as insidious and much more common: for every scene where Matt Dillon brandishes open racism with his personnel officer, there are thousands more where both parties know that racism is what is driving the conversation, yet neither comes out to say it.
As much as the film-making trusts its audience to put together pieces of different story lines, the dialog doesn't trust its audience at all. Not a single act of racism slides across the screen without a spotlight and flashing arrows.
Keep track of the stories, but don't worry about the point of any given scene: you can't miss it.