Here in Colorado Springs there is a thriving pawn shop and flea market industry that runs largely on stolen property. Two important sources of goods are the house construction industry (used tools) and the military bases in town (surplus military items). This has been going on for a long time, and at one point you could even go to the flea market and ask for specific "surplus" part, then return the following week and buy it.

A side effect of this is that the police department keeps a pretty good eye on the pawn shops and flea market dealers, and this spills over to the surplus metal market. I was at a metal store recently and asked about this, and they said that they get regular visits from the police department to remind them about the need to stay legal. The main recycling place here won't even buy copper any more.

So that brings up my question: What do you do with a stolen manhole cover or house plumbing pipes or street lamp wire? Somebody has to be the buyer. It's not like fuel that can be sold on a retail black market, because not many people are interested in manhole covers...