For me, if it the case of the nearly unobtainable stuff, I would grab a copy, especially when it is part of a collection. Then if the real thing comes around then I get the real thing, it is a collection after all!
A good case in point, I had a copied version of Dan Reed Network 'Slam' for years before finding a copy on ebay. It let me listen to a great album until I completed the set but nobody other than the previous owner made any money on it.

If you believe the RIAA, then we should not even be allowed to sell second hand DVDs or CDs now.