Apple's logic is similar to a strategy initially employed by News of the World when the phone hacking scandal broke. They said that they were doing it for the public good.
Well guess what. You don't get to decide you're allowed to break laws for the good of the public. The laws are laws, and you have to obey all of them. Whether or not you had good intentions is irrelevant.
Price fixing is illegal. Apple colluded to fix prices. Thus Apple broke the law. This is all that matters.
If Apple wants to claim they did not collude, that's a different story, but saying they should be allowed to do so is just going to hurt their case, just like it did for News of the World.