If piracy isn't theft, as is often repeated in the comments, then people need to stop referring to GPL violations as stolen GPL code.
Music 'piracy'(Unauthorized copying has nothing to do with attacking a ship on international waters): Little direct loss, as most who copy without authorization(especially since the advent of iTunes et al) wouldn't buy the music if P2P and such didn't exist for any of a myriad of reasons, and they would be that more likely to buy some other albums of the band whose music they copied(or even the music they took--remember that much of the stuff you don't pay for isn't that great quality), and they would also be more likely to see the band live if it's touring, something that gets much more money to the artist than record sales. And by the way, artists are divided on music copying, from what I understand the Red Hot Chili Peppers, for example, were more pissed that the leaked copy of Stadium Arcadium was low-quality than anything else.
GPL violations: Clear direct loss, as whatever changes Violator X did are not visible to the community to inspect and improve upon. No gain to anyone except Violator X, and that's only really short-term. What Violator X did is much closer to theft than what Copier Y did. As for your comment about mods, I have seen +4 or +5 posts advocating everything except the GNAA.
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