There are a few authors that get incensed by filesharing/copyright theft, F Paul Wilson is one. He's a hard working guy and what he would call a 'mid-lister', meaning he can't just rest back on his laurels and let the money roll in -- he has to keep working at it. His books have been pirated, and he (understandably) feels outraged by it. Here's him working hard while people steal his goods from under him.
I tried to make him feel better about it by telling him every theft isn't necessarily a lost sale -- many of the filesharers are like kleptomaniacs. They get a kick from having thousands of files on their comp. Some have terabytes of media. Way more than you could ever actually view/listen to in a lifetime. To buy it all, they'd have to be a millionaire. So, yes, it's theft, it's wrong, there's no plausible excuse for it, but it happens, and you can either accept it, embrace it and try to turn this aspect of human nature to your advantage, or you can let it get to you and make you feel like a victim. FPW can't get past the outrage he feels at seeing his stuff stolen and distributed without being able to stop it. I can understand that and respect it, but to my mind it's futile. If you can't change the thing that's bugging you, you have to change the way you think about it -- that's the only way to find peace, IMO.
I've also seen authors saying their sales increased after their work was taken onto filesharing sites. Carleton Mellick III is one. I think it probably depends upon how many titles you have out there. If you give away one, you might find people checking out the others. Even if you've just got the one piece out there, some people are decent enough to support the authors they like and buy a copy, and all the time your name is out there and people are talking about your work, you're building a fan base, so there are more people out there who will be looking out for your next story. I think piracy probably benefits unknown authors more than it does well established ones. I think the latter may well lose a few sales through it. Not as many as they think, though. A stolen copy doesn't translate directly to a lost sale.
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