For starters, it is a two player game. Secondly it will not always be crystal clear that you chose "defect" to your coplayers in the real world, since actions are subject to interpretation. Third, the real world is not a game of perfect information.
It is clear that you chose "defect" in the real world.. over time. It is in fact theoretically impossible to escape this consequence as time approaches infinity. Think about it, you are constantly leaving traces of you "defecting" and not leaving traces of not defecting. Eventually this catches up. This is also an example of the principle of karma, aka cause and effect. You can't escape fundamental effects of causes forever.
