Likely re-rendered for the 3D conversion. Or maybe they grabbed the wrong filmout file?
Yes, I thought the same thing.
But I’m not sure: the theatrical scene has more depth than the BR re-rendered scene. Furthermore, other scenes would have also deserved a new rendering for 3D (final battle in space, pod race) but yet they have not been re-rendered.
Anyway, you’re right: it would be great to have that released on bluray one day.