I've read its origins have "spread" across the galaxy some... Forget where I read that. Dathomir is what I'd always recalled as its "original" planet though, for what that's worth. Maybe they're just domesticated and used on other worlds then for various purposes.
I always kinda felt like Felucia was an uninhabited world by anything sentient, so I find Felucians sort of surprising themselves. I'm anxious to see this set though, and not really bothered by the concept... I guess the FU line's not bugging me much at all really, and after seeing the Evolutions set, I'm pretty happy with what I see. I just hope the game doesn't blow.