The side effect of privatizing what could be a public good is that is means denying to billions what they could have for free so that a relative handful will have an incentive to pay for it.
This, exactly this. Moreover, I think that piracy mostly happens because either it's the only way or because it's way too cheap. The first case is similar to how I was as a kid: I pirated all my games and software and copied all my music, and then bought the best games and the best albums that I could afford . I owned the games and cds that I considered the best, and worth owning. I paid for them so that I could own…
I think this is (close to) the case of people who are actually a problem. The first two cases don't represent much lost oppurtunity. In this case, the people pirating might go out and buy the stuff. Because of this, the oppurtunity cost of them already having some of the stuff is far more significant than in the first two cases (where there was minimal oppurtunity lost)