When you think about it, a commercial airliner doesn't really need windows for the passengers. Why do they need to look out? Indeed, the borders between the windows and the fuselage actually create engineering weak points, so from a practical engineering standpoint, the plane is better off without them. But just imagine what it would be like to fly from New York to Los Angeles in a plane with no view outside. And even then, at 40,000 feet, there's very little to see. It's just knowing there's an "out" out there. They serve little practical purpose beyond that.
The original Mercury capsule had two small portholes and a periscope instead of windows. The astronauts insisted that it have a window, and they won out.
But yeah, windows on a starship are for purely artistic purposes. In space, they would have no practical worth at all.