There definitely is a demand, and there are multiple threads where this has been requested and tested, but no one had yet devoted the energy to completing it. Believe me, there is a desire.
Absolutely there is a demand. Being able to have access to the deleted scenes of Star Wars, particularly when they have been cleaned up and look as good as new, is many a fan's dream to see re-integrated into the movie. That goes, not just for this franchise, but many other large films as well — reintegrating deleted scenes was so in demand for The Lord of the Rings that New Line Cinema offically re-released extended editions of the entire trilogy!
Now that being said— obviously, there isn't such a demand that any Regular Joe would want to see them. But Regular Joe isn't a fan. Regular Joe doesn't read websites like originaltrilogy.com, nor does he really care. But he's not the demand here; the demand is made up of all the people that love this stuff and do, in fact, seek it out.
For example, someone ripped the deleted scenes (in poor quality) off of the Blu-ray for Return of the Jedi and uploaded them onto YouTube. That was just in the last three months since it was uploaded, and it has more than half a million views!
There is, without a doubt, a demand see this footage. And if the scenes were cleaned up and looking as good as what you folks on team_negative1 are doing, you can absolutely bet that people would like to see them re-integrated into the films. Whether it be through fanedits or otherwise.
I'm actually working on my own fanedit of Return of the Jedi, where I've taken two deleted scenes (Luke building his lightsaber and Jerjerrod's Conflict) and reincorporated them into the film. They're brilliant scenes, and while I understand why they were removed, they add deep meaning to the characters presented in them.
I would love to see these scenes in a higher quality so that they might look more "in place" among the rest of the film. And I think all those that will watch these fanedits would feel the same way.