Then perhaps its time to disrupt the cable market...exactly like we've been seeing over the past 24 months.
I felt this way the second I saw XBox Live. Imagine how much more content you would be willing to consume from there if everything wasn't a la carte. You have a captive audience where you can charge advertisers a premium for getting in front of those eyes.
Instead the customers are asked to pay a monthly fee just to access online content and you either pay per download or for a secondary service.
Source: Facebook's stock today.
Edit: Also the cable companies only own a small number of the channels they broadcast therefore the ad revenue from those may be zero.