I once read a paper that dealt with Soviet economic planning, and among other things it talked about this phenomenon of mid-tier economic managers tapping into an inter-managerial black market, not merely for their own aggrandisement, but also to make their own economic units function better. Suppose they needed some cement, or some train cars, or whatever, and the economic planners at the top are once again incapable of interacting with reality. They'd bypass their bosses and go directly to the source.

If I figure out what the paper was called, I'll try and link it.