anyone running a brake on a non machined rim?



That's how it used to be done on any bike.

I don't know if there's anything special or unusual about the current crop of anodized fg/ss rims, but I have used a practically new '85 Schwinn, a 2001 Raleigh which had nonmachined rims, a rim on a c/b cruiser I added a brake to, and am about to start a NOS Gitane criterium. All of those bikes had an as-anodized finish on the brake track.

It's for looks. The wear doesn't look even unless it occurs on an equally shiny machined surface.
 
Jared from BMC in Cape Town is runnning a custom Monoq with powdercoated Velocity Glowdot rims, and a front brake. The braking surface is cut up, but the bike stops.