Thanks to their respective deals with on-demand distributor Epix, both Amazon.com (AMZN -3.18%) and Netflix (NFLX 0.01%) will add Marvel's The Avengers to their catalogs after the DVD, Blu-ray, and digital download sales window closes for the film.

But that could be months, and audiences aren't eager to wait. The Avengers topped the DVD sales charts for the week ending Sept. 30, according to Nielsen's VideoScan First Alert. Time Warner's (TWX) Batman: The Dark Knight Returns -- Part 1 took second while Universal's Snow White and the Huntsman took third.

What's surprising here isn't the sales data. Writer and director Joss Whedon's team-up tale resulted in a $1.5 billion box office haul for Marvel Studios parent Walt Disney (DIS -2.06%). A flush aftermarket seemed all but inevitable, especially in light of how well Lions Gate's (LGF-A -0.75%) The Hunger Games has sold on DVD and Blu-ray.

What's interesting is that Blu-ray accounted for 72% of Avengers sales while 3-D, still mostly a failure at the regular cinema, managed to capture 23% of purchases. Audiences are willing to invest in premium home viewings.

Still, why the sudden interest in Blu-ray? My guess is the add-ons. Disney confined a heaping helping of deleted scenes and fanboy-specific featurettes to its most premium discs -- especially the four-disc special edition pictured below -- stiff-arming those of us who've refused to upgrade past DVD. It's brilliant, if also a bit frustrating.

Source: Marvel Entertainment.

And I do mean only a bit. As much as the fan in me wants immediate access to all the content that's locked up on the Blu-ray disc I can't play, the shareholder in me loves what Disney is doing here. Blu-ray is a highly profitable format with more than enough storage to include new and varied digital goodies with every special edition that comes to market, each one putting a little more profit in the House of Mouse's already-bulging pockets.