Why Are Dual Layer Discs Still Expensive?

In an age where I my backups take up several gigabytes, why are dual layer discs still so expensive?  I purchased a dual layer burning DVD drive at the end of 2004, yet 3 years later, the typical cost of a dual layer disc is still costs around $2/disc.  I have tons of data to backup (OS images, hard drive backups, GBs of photos, etc) and it’s not like I’m looking to pirate a ton of movies, so what’s the beef?

I’ve done some browsing around the web and there seems to be a ‘group think’ that it’s because the media industry doesn’t want people mass pirating their media.  I’m not sure this is the case since tools already exist to re-master a DVD down to 4.7GB, the capacity of a single layer DVD-R.  Others have suggested that demand isn’t there to mass-produce the discs that would result in a cheaper production cost.

Whatever it may be, I find it extremely irritating because spanning data across multiple DVDs is inconvenient.  I guess I wouldn’t mind paying $2/disc if there was a reasonable assurance that I would be able to recover the cost in the event that the burner produces a coaster.  In any case, it seems that 30GB Blue-Ray disc will become available before a cost effective dual layer DVD-R comes out at a decent price..