Pre-orders have become a standard marketing strategy for video game developers to sell more units. Pre-ordering ensures that units are sold before the game's actual release. This can prove risky for gamers, as many games can be misleading prior to their release with fancy trailers.
Buyers' rewards to taking the pre-order plunge are certain bonus incentives. Whether they're in-game or physical extras, sometimes (more often than we'd like to believe) we're presented with something so useless and completely out of left field, we're left wondering what the developers were thinking.