Usually these things come from copies distributed by the producers, and not from theaters.
Watching a bootleg lets the potential audience see the story but hardly with the quality that they would get in a theater, let alone the "remastered DVD".
This may bite into the revenue from casual viewers (who don't even want to pay a dollar to see it down the line) and maybe repeat viewers but many of the same geeks that download this are waiting camped out in line in costume.