I read somewhere that part of the issue is that smaller manufacturers like Electrocompaniet cannot afford the high Blu-Ray license fees for small production volumes.
So they turn to larger manufacturers and source the base parts and in effect buy the license for a much cheaper price.
I have not listened to the units in a side-by-side comparison, but EC does add a balanced output stage and upsamples both PCM and SACD. I think the Ayre DX-5, also based on Oppo, does the same thing.
For some, Electrocompaniet's improvements, its quality reputation, and its house sound are well worth the price over the Oppo. For others, not so much.