I think I'd have to argue that the development team simply decided to compress the universe for the purpose stated above. In order to properly represent the vastness of space, the majority of the game would be absolutely empty. The only places where you would see anything would be near planets. Here's something to ponder that sort of supports this idea. Look at asteroid fields. If anyone here thinks that an asteroid field would truly be as dense as they portray it in the game, think again. The distance between individual objects in, say, the asteroid field in our very own solar system, is miles and miles. Like with most space action games, the scale has been compressed to make it more exciting, more action packed, more filled with neat stuff. Carry this idea to the rest of the game and voila, you've got a compressed universe that works well as a game but isn't really an accurate portrayal of a real universe.

All that is gold does not glitter
Not all those who wander are lost
The old that is strong does not wither
Deep roots are not reached by the frost.
--JRR Tolkien