Every intrepid RPG player has done the dungeon crawl. Poking around ancient ruins looking for treasure or an important item while dodging the many monsters that make these places their home is the bread and butter of RPGs. The game designers, of course, are simply trying to create an interesting immersive environment for the player. Little thought is given to the backstory of the structures you're looting. Practical concerns like living spaces, easy navigation and easy access to the rest of the world are sacrificed for impressive fifty foot ceilings and walls that grimace and moan.