Yeah, not always, but very often. Everyone here is trying to downplay this, but I would say >80% of people (disclamer: pulled from my behind) torrent simply because it's free and if they can easily obtain it free rather than paying, then they will. The argument that people pirate because the paid options are shit, and if they were as convenient as torrents people would just pay for them, is rendered moot with the Steam counterexample. Content distribution is much more well advanced and convenient in games compared to movies, and people still pirate en masse.
Of course, all of us are really just talking out of our collective asses until we can cite figures from a study.