We live in a spiral galaxy. The galactic arms spiral around the core, spreading out the further away they get. And the stars filling those arms make interstellar travel possible. Literally. We couldn’t do it without them. Think about it. Yeah, you see what I did there, don’t you? Heh. The serious point is, it’s the gravitic pull of the stars that makes hyperspace work. It’s like on Earth. You can travel from Old Japan to America in a rowboat if you find the current. That’s hyperspace. We follow the currents. But there are no currents to follow when you leave the stars behind.