The world of George Lucas' Star Wars is one of exciting spaceships, out-of-this-world weapons and costumes and a cast of characters ranging from space
Cowboys to robot bounty hunters. Do these serve to tell an interesting story? Of course, but that is not their prime directive (robot joke). This world exists as a factory-franchise toy commercial.
Throughout the span of 6 central films, and the apocryphal milieu of films, books, cartoons and whatever that may or may not be considered canon by the holy body of LucasArts, we are introduced to more and more characters, many with some awesome accessories and pretty changes of costume. Is this coincidence? Not according to Lucas' collaborators on the films. Besides, who would write a battle seen between chicken-legged, robotic troop-carriers and a bunch of goddamn Teddy bears for it's story value?
The issue of ethics here, as with most things, is muddy. Is it defensible to create a film with toy sales as a primary interest? It's not a concept unique to Lucas, but from a film-consumer's POV, it's somewhat morally dubious, insulting and annoying. Many viewers generally don't like story to be sacrificed to sell action figures of Jar-Jar Binks to 8-year-olds (and some rather sad 30-year-olds.) Personally, I don't like to be treated like a stupid plebeian by a filmmaker who merely rips off Kurosawa.