Everyone (in the US) gets TV content from the major networks for free -- just connect an antenna to your TV. You can pay to get more content, and access to previous seasons, by subscribing to cable or satellite. Subscribing doesn't reduce the ads at all, just gets you more things to watch.
Hulu is an exact replica of the business model, except using the web instead of radio and cable lines, as the delivery method.
Everyone (in the US) gets TV content from Hulu for free -- just browse to their website. You can pay to get more content, and access to previous seasons, by subscribing to Hulu Plus. Subscribing to Hulu Plus doesn't reduce the ads at all, just gets you more things to watch.
The only difference is that a cable subscription averages more than 10 times the monthly cost of Hulu Plus. To expect to not only pay 90% less than cable, but also eliminate the advertising, is unrealistic.