Because software distribution through physical retail channels was well established before the internet became mainstream. And before Microsoft could get their

Because software distribution through physical retail channels was well established before the internet became mainstream. And before Microsoft could get their head around the opps on the internet, Tucows, CNET, et al. had the leg up in online application distribution - though they left monetization up to the end developer. Digital River used to be a digital download online marketplace, but they cut their "app store" out and now focus solely on e-commerce.