Games released via Steam have shown evidence that when a singleplayer game is unavailable as a torrent for free, then people will pay for it. The counterargument to this is that most people who torrent wouldn't pay for it anyway. But I assert that there is a third class of people: those who first check to see if it's available for free, and if not, pay for it. Whether these people constitute a significant portion of revenue is an open question, but it's hard to classify their actions from a moral standpoint as something other than stealing.
The closest classification other than "stealing" would probably be "sampling." I've often been frustrated at an inability to try out a certain kind of dev tool before buying it outright, and their free version is usually missing features which I really need to test. But there needs to be a large-scale study as to whether people really behave this way normally, or if they just take what they can get for free. Unfortunately it's difficult to find an unbiased source of funding for such a study, so the resulting research paper would probably be slanted in one moral direction or the other instead of presenting the raw data.
It's not an easy question to answer. I think technological capabilities will decide how companies will behave, because those who don't accept reality will go out of business.