Vudu is a distributor. Their contracts are with studios. This situation is not covered by Vudu’s terms of service with you, but by their contract with the studio. With digital content, studios have finally achieved with home media what they have always had with theatrical prints. The content belongs to the studio. Not to the provider. Not to you. The only way to be sure you keep a particular version of digital content is to capture and save the stream to a device you control. That they cannot change. But the studio changing content is not up to Vudu or any other streaming service. Your gripe is with Disney and Lucasfilm because they are the ones who did this. Any other studio can do this at any time. The studio can pull a title at any point in time (though I suspect that is covered by their contract with the distributor and not too likely). Case in point is Starz disappearing from Comcast overnight.
You are getting mad at the wrong people if you get mad a Vudu, YouTube, iTunes, or any other streaming service for this. And most of us have been rather excited for this change to propagate through all the systems. I perefer Maklunkey to the oversaturated magenta mess than was the 2003 transfer. Frankly, until they switch it back to the original where Greedo doesn’t shoot at all, I don’t really care what version of that scene it has.