Its freedom in exchange for comfort: the casual user no longer has to worry about looking for software because there's a large corporation telling him what he can do and what he can't.
For many freedom of choice is stressful, but receiving orders is not.
It's also cognitive load. Facing infinite options with no guide isn't great. You don't read the entire internet, and likewise you're not looking for all options when looking for an application. Apple hosts all iOS apps, they have to sell the prospect of an open platform, so AppGratis acted as a filter.
Much of the paid-blogosphere is acting as a similar filter to this end. BoingBoing, waxy, and other early-web popular aggregators are known for reliably pointing at new-and-cool, not for being cool. Now blogspam aggregators are a business with margins.
For many freedom of choice is stressful, but receiving orders is not.