Sometimes (one example being the Lawrence Of Arabia restoration) a niche product generates it's own demand.

I remember seeing that in the theater where even with the rough edges caused by the age difference of some of the actors re-dubbing the restored footage it was universally well received and then being first in the queue to buy the VHS of it which sold out at my local HMV branch very quickly.

It was also one of the first DVDs I purchased and it was a handsome set with some nice extras and I paid a premium price in the day to get it on my shelf as soon as I could.

By now any Star Wars release is going to be to some extent a niche product as almost anyone who has an interest in seeing the 2004 version of the film would have seen it many times and been purchased many times and it's no stranger to broadcast television even in HD.