Apple has never allowed ad-blocking software on the iPhone or iPad. This is one among many reasons that I ditched both. Not because I hate ads all that passionately, but because it's an example of the obsessive corporate control Apple maintains over its environment.
TV can reach broad audiences, mass audiences, niche audiences; it can be local, regional, national; it can be spots, sponsorship, interactive. It can be anything you want it to be. I tend to think of TV as the Swiss Army knife of media, it's got something for everybody.