Downloading music off the interwebs doesn't deprive someone the ability to sell something. If I steal a car, the person from whom I stole that car can no longer sell the car. He no longer has it, so selling it would be tricky. On the other hand, if I design a machine that makes instant copies of cars, then use it to copy a car from a dealership, the dealership can still sell the car I copied, because they still possess it. Now, you might say, "But they can't sell it to you! You already have that car!" Which is correct: copyright infringement theoretically lowers demand. But then, what if I wasn't going to buy that car anyway, and so my demand was already zero? In fact, maybe driving that car has made me desire a car from the same manufacturer! Maybe I like it so much, I'll pay for the next car I obtain from them. And perhaps if I designed this wondrous machine, it would not be so morally outrageous if I used it to copy cars that the dealership no longer had any prospect of selling in large numbers.
Of course, I'm not just speculating. Research shows that people who download music illegally also
spend more on music purchases.
