In the past couple of years Netflix and Amazon have entered a territory previously untouched by on-demand services. They are making their own TV shows. And some are turning out to be really popular like House of Cards, Orange is the New Black and From Dusk Till Dawn. Like network TV, not all of them have been popular, Zombieland was canned after a single episode. Have you checked out any of the shows made by an on-demand service? Would subscribe to one of these services just to see their exclusive series?
I have never heard of an on demand service before. Though I have heard positive feedback about Orange is the New Black. I wouldn't consider subscribing to a service like this unless the price was reasonable.
I tried a 'one month free' offer for Netflix once, but they didn't really have anything I wanted to watch at the time. That is likely to change, because all of the Marvel superhero shows they are producing are shows I will want to see. So although I haven't subscribed to one of these services yet, I suspect I will be in future.