1 Iki Piki: We can't sell our spare organs. They'll be the only thing keeping us alive when we come back in time.
1 Serron: Only one thing for it. We skip the system without paying.
2 Iki Piki: We'll be branded as criminals across an entire section of the Galaxy!
2 Serron: You mean "sector".
3 Iki Piki: No, a sector is a piece of a circle enclosed by an arc and two radii. They don't tessellate. That's a stupid way to organise a galaxy into administrational units.
4 Serron: Oh, and I suppose you've been branded a criminal across one before?

Taken geometrically, a sector really is a silly shape for splitting up a thing as large as a galaxy into administrational or navigational sub-units. You can get three or four sectors which make convenient sub-units, but each one would have bazillions (yes, that's a technical term) of stars and be of marginal utility beyond considering the galaxy as a whole. What you really want is cubical sections roughly tens to maybe hundreds of parsecs across, so each one contains a workable number of stars. You could fit about a million to 10 million such sections into a typical galaxy.

This is taking it literally of course. "Sector" has effectively been neutered of its geometrical meaning in science fiction.