I think a lot of it stems from how Apple has handled their customers over the years. They have built a loyal following by offering top quality products and backing it up with almost flawless service. That builds loyalty, much like what you often see with people and their favorite sports team.
Treat people right and they'll have your back.
This is startlingly naive. Corporations are machines for making money, first last and alway -- and they behave accordingly. They are interested in you precisely to the extent that it benefits them and no further. If people assume that a corporation is good and right just because they like their products, then they are missing something fundamental about how this bargain works.