Maybe Ewan doesn't hate Star Wars. A little video up on YouTube from an interview on BBC, where he speaks pretty positively of the experience. I suppose it depends on the day.
In contrast to the other actors, I think ewan is more of the rare "I'm going to do a great job of acting regardless of the directing" type of actor, alla Johnny Depp or maybe even early Harrison Ford. I'm sure like any job, there are things he liked and things he didn't like - I bet most of us would have contrasting opinons about our jobs depending on the day we were asked.