Where I come from, both parties have to consent. The buyer says "I purchase this for $10". The seller says "I purchase for $10." You have a valid sale. Modern f

Where I come from, both parties have to consent. The buyer says "I purchase this for $10". The seller says "I purchase for $10." You have a valid sale. Modern forms involve giving the money, then getting a receipt. Here's the problem - the seller can be a thief. The common forms of seller theft is selling something of less value than marketed, or with conditions that were not brought up earlier (like no repair). Being illegal isn't be the only measure of theft, not in some societies. You can pirate something without theft -- as long as the seller consents to it. It won't be legal if there's no written agreement of consent. Some companies have this model where you can illegally use their software forever, but have to pay for a license. They want some of the richer people to pay, but the law doesn't recognize this selective consent, so it's enforced selectively. But in OP's case, there's no valid transaction possible in some situations. They're not pirating nice guy WinRAR. The seller doesn't want to consent and the buyer won't consent. Because there's no possible option, the pirate assumes it belongs to nobody and takes it. Thieves will often justify a theft, either by saying nobody owns it or that it belonged to them. There's a whole hill of philosophy here about what private property means. Taking back your homeland is not theft, because it's yours. That's why we have laws so a third party can judge these things. But you know, maybe just come to terms that stealing isn't always unethical. Instead of saying piracy isn't stealing, it's more like piracy isn't unethical. It's pedantic, but solves a lot of the nitpicks people have on the topic.