Because Klingons were backburnered to get the game out the door quickly. Don't be surprised if Klingons are the first paid expansion.
That's possible, although I thought that Romulans were already promised as the first. Oh well, just curious. The sectors don't seem to be close to what is in Star Trek, but I guess they are interpreting it their way.
Of course, could be cool to see Klingons take Federation sectors as the game progresses!