Games are one of the most sophisticated forms of escapism. Virtual game worlds fill our imaginations the same way a good book does. Increases in graphical quality over the last few decades have allowed game-makers to add an astounding level of detail, making them even more immersive.
Traditional graphic design exists as an idea on a screen or printed page, separated from a real world context. Sure, there are often elements of interaction but it largely exists as a concept. Environmental Graphic Design (EGD) is how design behaves in a physical (or virtual, in our case) context. It includes things like wayfinding signage, architecture, and branded spaces.