Here is where retailers are short sited on the 30% to Apple. If this had been an in app purchase, I would have tried this service out. I will not sign up for this on their site, have another credit card and password I have to manage (especially when I get identity ganked again) so instead, they will get none of my money. They are really overlooking the benefits of an already established account that is easy to access.
Wal mart has an enormous influence on retail.
The promotions they could run to get people to use their service are endless.
Everything from spend X amount of dollars get a free movie, by a game console, tv, dvd playet get X amount of movies free.
Once the person is signed up the convenience of the service is established.
How do you keep people coming back, another promo.
Perhaps they won't make a ton of money on the service, however they could easily make up for it in the amounts the consumer spends at their stores and site.