Now, excluding the series in question, think about the major themes and elements that make a story a Sci-fi versus a Fantasy.
SCIENCE FICTION...
uses technology of the possible future, based in the theories and dreams currently, to mold a plot where the dilemma is caused or possibly fixed by technology. Many stories of the genre have themes involving humanity, society and moral ambiguity. A great example of a Sci-Fi movie is Blade Runner. For a literary example, let's go with Brave New World.
FANTASY...
uses a world where forces beyond scientific explanation and many times is mastered by an innate intuition of how it interacts with the world. These forces are used to explain phenomena in the world, as well as a major plot device for progressing the main character(s) goals. Many stories of the genere have themes involving good versus evil, family inheritance, and an epic journey (either internal or external). Both The Lord of the Rings and the Harry Potter series are great examples of fantasy books turned into movies.
When it comes to themes and story progression, Star Wars has a lot more in common with the Harry Potter Series than it does with Brave New World, Star Trek or even Firefly. It follows the journey of a young man who has to come to terms with a great power within in, and how to rectify the evil brought to his home without him even pursuing an adventure. He's inherited a gift from both his parents that he uses to see and change the universe around him. He has to believe in it first to work, and then he has to use that power to defeat one of the greatest evils ever known. I just described the stories of Harry Potter and Luke Skywalker in the vaguest terms. They really do have a lot in common and should go get some tea together.
"Set in space" does not mean "Sci-fi". "Aliens in space" do not mean "Sci-fi". There's a lot more to it than technobabble. And I'm sorry, the addition of the force being "aliens in your blood" rather than just a mystical entity does not change the fact that science is unnecessary to any Star Wars plot.
Now this is not to say that the worlds cannot blend or meld into one another. Strange, inexplicable things can happen in many sci-fi stories. Fantasy will utilize science from time to time, especially if it's in a modern setting. Usually though, the way the plot focuses on and resolves the main conflict is the key to seeing what a story is when it comes to these two genres.
Talking about this with my friend Proptart, she classified it as a "Sci-fi Fantasy", wherein there are some sci-fi elements in the story (space travel and such) but the story itself is of the fantasy genre. Although I would accept this classification, I would prefer to go the extra step and call it a "Space Fantasy"--a fantasy story told in a galatic setting.
I doubt Blockbuster is going to rearrange their layout for that classification.
