Paying for the service and then paying again to rent the game is a bad deal. It's why On-live failed and it doesn't make me hopeful for this service.
Oh, I fully expect this to fail. This is an excellent point you make, but just how much bandwidth do you need for the streaming for it not to lag and/or have poor image quality.
This is feel-good nonsense so they can look like they give a crap about BC for the first year or so. I give it that long to end up like gameroom.