You know what really annoys me? When I spend money on a DVD and have to sit through an advert at the start telling me piracy is a crime. Why tell me? I paid for the disc. I imagine that if I'd illegally downloaded a movie, the pirates would have deleted the piracy warning.
Exactly. Apart from legal issues, downloading pirated stuff is much more convenient. It's usually region free, you can watch it on any device that can handle the video format without the need for a DVD drive, no anti piracy warnings, no previews. Worst of all is when these warnings and previews are unskippable (on a standard player)
Some time ago when I visited my parents I brought a DVD with me and we watched it together. She was quite irritated at the anti piracy advert saying: "Why is it showing this to us? We have bought the DVD, haven't we?".