The (movie/audio/warez/demo) "scene" is not anarchic at all but rather a very well organised distributed processing machine. You probably know these guys organise into "groups" but there is lots of other stuff you likely do not know. I will describe below aspects of the warez scene, as it was some 10 years ago. I believe most observations continue to hold today and are probably mirrored in the movie-release scene. So:

"The scene" is made up of groups and each group is made up of specialists: suppliers provide material for release, crackers (or rippers, depending on context) remove copy protection and sometimes optional "filler" material, coders write useful helper software for the group and couriers distribute releases around the internet. Not all groups fill every role and some may have other roles I did not describe here (hackers, carders, hardware suppliers to name a few). There are sometimes partnerships between groups with different specialities; usually this occurs when there is an overlap in membership. For example: a release group may have close links with a particular courier group and those guys handle all their releases.

The distribution process is actually quite interesting. Each successful release group aims to have a small list of affiliations with well known and prestigious underground boards/ftp-sites. The quality and prestige of a board depends on the speed of its connection, its capacity, its group affiliations, the standing of its admins in the community and the speed with which new releases are uploaded to it. Each well regarded site is allowed only one particular kind of affiliation: a games group affil, an apps group affil, a courier affil, an ISO affil -- you get the idea. The important thing is that there is only one of each. Affiliations carry prestige for a site and being affiliated with the best sites raises a group's prestige, so there is often heated competition between sites and groups for affils. This is the case at least in the so called "zero second" scene where releases are "traded" (i.e. re-uploaded) by couriers within seconds of being first uploaded. Once a release has been traded among all zero-second sites, they slowly filter down to lesser and lesser sites until eventually making their way to the Internet at large.

So why would you go this all this trouble? The reasons are myriad but usually it comes down to prestige: for example, among couriers there is a longstanding weekly and monthly competition between groups that prove their chops by trying to dominate each other. Similar competitions exist among release groups. There is huge pressure to be the first to release a highly anticipated game or well known application. Additionally, there are strict rules about how to release something -- what to keep, what can (and should) be omitted, how to package everything up, the inclusion of .nfo and .diz files and so on. Failure to comply with these strict standards renders a release invalid and causes it to be "nuked" (deleted) among the top sites. This process amounts to a public shaming of the group responsible and makes it possible for competing groups to snatch the credit by doing a "proper" release.

I could go on and on but I think that's enough for now. Hopefully I've convinced you that pirates aren't an anarchic bunch ;)