Apple do not charge for a streaming service. Apple TV is a platform that lets you install -- as apps -- the streaming services (or "channels" in cable speak) you are subscribed to. Most streaming-enabled channels are available via Apple TV, but not all. They don't support arch-rival Amazon's Prime video service for example.
(As a Prime customer, I get around this by running the Amazon video app on my iPad and use AirPlay to transfer the movie from my iPad to my TV via Apple TV. I do the same with YouTube. YouTube is a PITA to run on Apple TV but works great on iPad -- for searching and browsing, etc. So I run YT on my iPad and AirPlay it to my TV. It's beautifully integrated. I do the searching and browsing on the iPad and the content I play pops up on the TV.)
Eventually a Apple WILL offer a bundled streaming service for a monthly fee. They're negotiating with the content producers right now and within a few months intend to offer Apple TV owners about the same variety of content as the cable companies offer now, including network television.
The cable companies have had a monopoly until now on both the signal and the content, and used that monopoly to royally screw American consumers: for example, making us pay for garbage channels we'll never watch in order to get the ones we do.
Because the Internet is the delivery medium for streaming channels, the cable companies have lost control of the signal and competitors like Apple are about to give us couch potatoes an opportunity to escape their greedy clutches.
I haven't used cable in years because with Apple TV, a fast Internet connection, and access to other content via my iPad, I've got more quality programming at my fingertips than I know what to do with.
But then, I don't watch football.
Cable's last holdout is stick-and-ball sports. They've teamed up with NFL, MLB, NBA, etc. (via ESPN and other jock channels) to generate billions in revenue for the teams, the leagues, the advertisers, and of course themselves. All paid for by the poor schmuck with the $190/month cable bill and yet STILL has to endure endless commercials to get through a game.
All that is about to change. Some day, maybe soon, maybe not, you'll be able to fire up your Apple TV, switch to the NFL app, and watch the day's games in real time. Because they're apps, you'll be able to watch games, movies, TV news, whatever, on your TV, your iPad, even your iPhone. If your home's WiFi network is healthy, Apple and other Internet content providers will free your viewing life from being packaged in the form of a giant ripoff by the cable industry.
The cable industry is not taking this lying down. At this very moment they are fighting the FCC for control of the Internet. But they're not going to win because America's consumers now have a CHOICE and they're not going to give it up without a fight. (Unless the Republicans with in 2016, in which case all bets are off!)