Ethics of Star Wars

I was watching Empire Strikes Back the other day, and something one of the characters said struck me. Chewie is choking Lando, who’s trying to gasp out “Han! There’s still a chance to save Han!” Chewie finally lets him go, and off they go, running to save Han. While Lando crouches, trying to recover, Threepio (who is half assembled, and strapped onto Chewie’s back) shouts out “Don’t blame him! After all, he’s only a wookie!”

Only a wookie? It struck me as a little racist. Or, more accurately, speciesict. Who’s to say one species of aliens is preferred over another? Let’s say, for example, all the Star Wars characters were stranded on a desert island somewhere. Would it be wrong for them to kill Chewbacca and eat him? What makes him different than, say, a cow. How do people who live in a multi-species universe decide which ones are “people,” which ones are “food,” and which ones are lesser species; not food, but “only a wookie.” Even Luke used to bulls eye womp-rats in his T-16 back home. Why isn’t that murder?