On this wheel the brake side hub bolts on and the right side hub is an integral part of the wheel. I'm guessing the bit extra in material/cash to do both integral wasn't worth it to him...
Mike and Doug over at MAD did a beautiful job with your wheel brother! Congrats on going the full 3D route.
I bet Felix! I saw pics of that on facebook and was VERY impressed. Mike is an amazing machinist and designer. Doug's not such a bad guy either. Congrats again. Can't wait to see it on your bike.