I'm not sure exactly what you are trying to compare. Rather try to compare those who simply pirate the stuff as soon as it's out with anything of the above. I think if they'd offer something around $2-$3 per episode right away (without any iTunes), they could gain more from those who don't pay anything to them now.

I'm comparing the amount of money HBO would get from people who only watch Game of Thrones. If you could get it without subscribing, a lot of people would cancel HBO.