Have you ever thought of saying screw the system? What if you ordered items online and when the delivery person leaves them on your doorstep, you claim you never received them? What if when checking out at one of those self-service checkout registers, you took a couple of items each time without paying? What if instead of paying for films and music, you downloaded them for free from file sharing websites? (Everyone pretty much does that already).
What's the point of following rules if the games is stacked against you? You're just going to lose anyway. That was the lesson in Ender's Game. If Ender Wiggins followed the rules, he would lose, so he ignored them.
If you haven't read the novel or seen the film, I won't spoil it for you by telling you what happened. It was a great novel. You should definitely read it for yourself.