I think the money laundering thing is orthogonal.

Koons is the prototypical example of delegation (to carefully selected artisans), but many less notable contemporary artists delegate realisation to fabricators (I have seen this first hand only in sculpture.) I think the fact that this is now acceptable has something to do with the decoupling of visual art-as-concept from art-as-object that has occurred over the past 150 years. The rise of CAD also makes it easier to design a work and delegate fabrication. Of course Music and Theatre have been delegating realisation pretty-much forever.