Part of the squick here, I think, is that in the old Flash Gordon comics, even though Ming the Merciless (or King Vultan of the Hawkmen, or whoever) frequently had Dale Arden dressed up in a harem outfit, you could always be absolutely sure that the villain would wait until after a proper marriage ceremony to "take advantage" of the heroine. But this ceremony would of course never actually come to pass, due to it being foiled by Flash and friends.

Kasdan's Jabba, on the other hand, is a creature of our modern world, where chivalry is dead. He doesn't belong to the knights-and-spaceships, capes-and-rayguns archetypes created by Edgar Rice Burroughs before WWI and continued by Alex Raymond. In the latter type of story, we can enjoy the heroine being forced into skimpy outfits (or, as with Dejah Thoris, casually gallivanting around wearing nothing at all) and still not fear for her safety; in the former that is impossible.