My mother was a publisher. From time to time, someone would market unauthorized copies of her books. They paid no royalties. She had no practical recourse, but what they were doing is stealing.No, you only deprive anyone of anything if you would have bought it if you didnt download it!
This is the major thing that i.e. record companies completely fail to understand. If I download a song it does NOT mean that I otherwise would have bought it, nor that they lost a million usd because I did, which they seem to think. At best they lost the ammount THAT ONE SONG is worth and at worst I wouldnt even have listened to it or their band at all..
Copying one song or one copy of a program for your own use is such a petty matter that nobody is likely to care much. But marketing unauthorized copies, or making it easy for large numbers of people to download unauthorized copies, without paying royalties, cuts into the author's royalties and the authorized publisher's profits. In this case, maybe some people will download who would not have purchased, but others who would have purchased will take the free download instead.
What it really comes down to is this philosophical question: If I create a novel, or a poem, or a song, or a computer program, do I have the right to withhold it from anyone who won't pay me for it, or does every novel written, every song composed, every computer program created, automatically and immediately belong to the entire human race?
Your argument is that if you are not hurting anyone, it's okay to use someone else's creation. It's a fundamental philosophical question of intellectual property. Is there such a thing or not? And you conveniently ignore the impact on the author's livelihood of unauthorized mass distribution of something someone else created. Authors provide something of value, and they can do this only if they get paid for it, and royalties are the way they get paid. You are telling the author, "I liked your song enough to download it, but I don't think it really has any value, so I'll listen to it without paying you anything." If you like the song well enough to listen to it, the decent thing to do is pay the author his royalties.
You assert that it is morally justified to use someone else's property as long as they do not lose by it. This is a convenient justification to not pay for what you use. What if someone opens your garage during the night, and takes your car out for a joy ride. They replace te gasoline they burned, and put the car back. No damage was done. The wear and tear on the car was minimal. (Like the royalty you didn't pay for one song.) Should that person's right to use your car while you are not using it be protected?