I'd have to look at the numbers to see how things have sold over the years, so let me just say something about the '04 dvd. Many people, myself included, were just so distracted by all the bells and whistles and just the sheer fact that the movies were finally on dvd at all (after the first two prequels had already been released on the format) that we just didn't care about its not being the original version. Now, not everyone shared this sentiment. Chud.com didn't even bother to review the boxset and a reader wrote the site's founder, Nick Nunziata, to ask why. Nick replied in his mailbag column with something along the lines of "oh, yea, it's been a while since I've seen those movies, so maybe I'll give them a watch."
He didn't write a review simply because it was the SE, and this is coming from a guy whose website reviews just about every dvd that gets released.
It goes without saying then that the Limited Editions were also not reviewed by the site. People have become turned off to Star Wars because it's just not worth it. They can't just be movies anymore. They have to be, as I overheard someone in one of my film classes put it, "a way of life."