Retail Dvd

How do dvd-rip torrents get released before the retail dvd gets released?

I see plenty of torrent websites full of “DVDRips”. These are torrents made from by ripping the media off of a dvd (like a movie). My question is how in the world do these people get their hands on the dvd BEFORE the rest of us do? How do they make a torrent from a dvd, when the movie is still at the theaters (and the dvd has not been sold yet)? Is it a fake? Not that I condone piracy, but just how do they do it? Is it an inside job? Do they work for the studios?
Extra question: Why do the studios hold back the DVD release if the DVD-rip torrent is already out there? Doesn’t that put a rush on the studios to compete with piracy?

Someone gets a hold of the film, usually someone who works for a theatre, and compresses it onto a dvd. So yes, in a way it is an inside job.

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