I disagree. I am supposing that the Blender file format, like the native MAX file format, the native MAYA file format, the native Modo file format (etc) stores a ton of useless information (i.e. useless to any program other than the native application). These native file formats are bloated because they carry such information as the precise position of the view ports (how many, where the view port camera is facing, etc) and a lot of other program specific data that no other program can use.

Export file formats are created for the purpose of getting what you need out of the 3D app for use in another 3D app or real-time 3D engine. It keeps the other app from having to be programmed to ignore the redundant data in the native file format of the app that created it.