A few weeks ago, I watched Return of the Jedi with a friend who is not up on Star Wars and hadn't seen the movie in years. Having a fresh perspective does wonders.
When we got to the meeting between Leia and Wicket, she said, "Leia seems a little condescending." Granted, Leia doesn't know anything about this creature or its intelligence, but why default to treating it like a child or a pet? (I think Leia has
internalized a bit of the Empire's racism despite her best conscious intentions, but it isn't necessary to think so here.) It could just be that the low tech level of the planet leads her to assume that any natives can't be that bright, the way Luke disdains Dagobah (and Yoda) at first because it doesn't have any "cities or technology."
The characters having prejudices isn't a problem at all. I don't expect them to be completely free of prejudice. What started to bother me once I was conscious of it, though, was that the narrative seems to share some of those prejudices. For instance, the Ewoks mistaking Threepio for a god is supposed to be funny and a convenient way to get the characters help for the battle later. But, um, it makes the Ewoks look pretty simple not to realize that their "god" is acting as the servant of people who look just like the bad guys down the road. Maybe that's why they didn't free their prisoners right away - to test Threepio? So then Luke uses the Force to convince them that Threepio really is a god, and they squeal in terror. The Rebels proceed to continue the deception (guess Threepio's programming isn't that good) and use the Ewoks to fight the Empire. Sure, the Ewoks have their own reasons for fighting the Empire, but I'd say that's ethically dubious. But the movie never has the characters worry about the ethical dubiousness, or indicate in any way that it isn't just fine.
I also realized that one reason the Ewoks' cuteness bothers me isn't that it's just... well, annoyingly cute. It isn't that bad, really. The bigger problem is that by making the Ewoks cute and credulous in the first place, it reinforces some nasty stereotypes about the Simple Native. I can come up with perfectly good in-universe reasons for the Ewoks to be impulsive, low tech-level, believe in Threepio as the avatar of a god, etc.. But since they don't actually exist, GL could have made them different. The Furry Natives could have helped the Rebels because they understood that they had a common cause, not because they thought Threepio was a god. They could have had less comic moments and not, say, clonked themselves in head with rock slings. Technologically simple doesn't mean "cute and clever but culturally and mentally simple." The Ewoks remind me of old movies about Native Americans which showed them as having "simple" lives and culture. You know, they're "closer to nature," so they're all noble and just sit around talking to the spirits or something - when they aren't acting as cannon fodder or sidekicks or lessons for the white protagonists to learn, that is. It's inaccurate and condescending.
On the other hand, this leaves many possibilities for interesting stories. What happens when the Ewoks see other protocol droids and realize they've been tricked? Or do the Rebels just take off with a "thanks, and hope the giant battle station exploding in orbit doesn't do anything bad to your planet!" Wouldn't the Rebels' treatment of the Ewoks make a great political weapon? Those who don't want the Jedi Order reformed would probably love to know that Luke used his power to manipulate a civilization into dying for the Rebels, for instance.