That design is actually for back-face culling. It's meant to block your view from a distance into the building so the game engine doesn't have to render it. Having to render the internal architecture and the external area all at once would kill most cards... except THE TITAN!! (semi-jk)
WoW even does it for their inns with an elbow entrance. That way you can have a F-Ton of toons inside and outside (aka: Goldshire (on Moonglade)).