Same as a lot of VW wheels, the outer rim is turned on a lathe after painting to achieve the polished look, then the whole wheel is lacquered.
The other option with Pescaras (which don't have the flat rim like Monzas and other polished rim VW wheels) would be to source the shiny trims BBS use on their black CHs. The may have to be slightly modified to fit (not much I reckon) but at least won't end up with whiteworm.