The problem isn't that Lucas is changing the movies, it's that he's attempting to remove the original versions completely, by making the Special Editions are the only versions available. He's denying the original versions their place in time and existence. He's trying to make it as if they never existed. He's trying to pretend that the Special Editions have always been around. If it were up to him, all the original versions would probably be destroyed and the Special Editions would be the only versions anybody's allowed to see.

He refuses to let the original versions have the treatment they deserve by only releasing the Special Editions. They really need to be released, so that in the future, film fans can see the original versions the way they were made. If they can only watch the Special Editions, they'll think that this was how Star Wars originally came out, that this was the original version. Without the originals, future generations will never be able to see how great, classic and (most importantly) extremely influential movies like Star Wars were created without the ease of CGI and modern day digital technology.

These movies need to be made available in their original versions, if only just for historical purposes.