My position on this is to come from the other end, i.e. start at the moral side then journey into the economic.<p>Economic laws have been developed over time for the good of society. We started to settle and farm so we needed property rights. This was so your hunt didn't kill my dairy cow - disrupting both our milk and cheese nommage.<p>Intellectual property rights exist then to  ensure that society has a good supply of IP. Their success should be judged not on the moral value of you 'stealing' my 'work' but on how the copywrite and patent systems changes supply and demand curves from the baseline that would exist without the extra rules (and costs associated with those rules).<p>Remember it was not illigal for you to hunt my dairy cow because of how unfair that feels. If I'd been keeping a friendly rabbit alive society wouldn't have bothered with property rights. Society wants more Meat and Cheese, not warm fuzzies.<p>So where does that get us? 
Well, does anyone truly believe they'd be music starved if they could only listen to the current back catalouge + what would be made for the kudos / enjoyment / profit from merch &#38; performing? No chance. Music should be free, we have a VAST oversupply and there are ample incentives to keep people supplying it without authorized monopolies.<p>Books? Movies? Games? With these the cost of production is alot higher, the argument that people would do it for free still exists but it's less obvious how they could leverage resultant fame into some kind of money spinning live performance. I think here society needs to have the debate, but for it to be useful it MUST be framed in terms of supply, demand and what behaviour the system incentivieses. Not self-rightious moral 'right' of what you 'deserve' either from the pirates or the artists.