By acquiring a duplicate of the original, you're no longer depriving someone of property in the way you would be with theft. If you steal an apple, that's one less apple that the store has to sell to someone who is willing to pay for an apple, and the store will still owe the orchard the cost of the apple you took. In contrast, pirating a movie doesn't remove any physical copies from shelves. The problem comes down to what you believe the cost of piracy actually is, and who bears that cost, which gets complicated in the case of digital goods and subscription models. If the argument is that piracy lowers demand in general, then you'd have to account for the effect of libraries, the secondhand market, and competition from other media. The practical evidence that pirates are outnumbered by paying customers suggests that on the balance, the system is capable of supporting some freeloaders without collapsing. To extend the apple analogy, it would be similar to people coming to the orchard after the harvest and gleaning the leftover apples instead of buying them from the store. Can you argue this diminishes apple sales? of course. Is it theft? yes, and the orchard owners have their right to insist it's a crime and all apples must be paid for, but if the apples were going to rot anyways the harm is minimal. Would it completely destroy the apple market and leave all apple growers destitute? I don't think so.