The media providers (NBC, ABC, CBS, ESPN, and any number of other letter combinations) and their partner distributions channels (Comcast, DirecTV/AT&T, DISH, etc.) have a vested interest in keeping you from getting your channels easily over your choice of streaming devices. Many of the aforementioned media providers and distribution channels are owned by the same companies.
Many many years ago, before we started down the dark road of pay television broadcast television was supported by commercials. And then we got the gee whiz moment when we started being allowed to pay for television that "didn't have commercials." But as time has gone on the media companies have slowly but surely worked toward putting the commercially supported, "free" channels (or more specifically the programming from those free channels that's worth watching) out of reach of their customers. The FCC requires that broadcasters still broadcast their channels over the air for free, but they would gladly stop doing that if they could. But they can't. So instead what they have done is move so much of the content that we used to watch "for free" supported by commercials to channels that you can no longer get without subscribing.
That's why you can no longer see your home town baseball team play unless you're willing to subscribe to cable or satellite (or act illegally). Were you aware that you couldn't even watch the MLB playoffs this year unless you subscribe to cable or satellite? Up until the World Series all playoff games were on pay television. Sure, MLB would sell you a live streaming package for a fairly nominal fee. But you couldn't subscribe to it unless you have an active cable or satellite account.
Most of what I wrote above is already known to a lot of people. But until and unless people look at the historical and evolutionary nature of television versus where we are today they get no perspective on what role their actions have in the grand scheme of things.
The only way that things will get any better is if we as consumers say that we are not going to play the game anymore. I, personally recently cut the cord on my satellite package, and get my local channels over the air with an OTA DVR. I will miss my local baseball team's games next year, and that will be painful. But I will no longer support a system that wants to put a meter on things that are also supported by advertising. It's time that we, as consumers start forcing real economic lessons on the video media producers, just like we did on music labels and newsprint companies.
I can guarantee you one of two things. Either there will be an Amazon app, or Jeff Bezos is engaging in childish behavior that is in direct contravention to his company's best interests. Every move that Amazon has made to date indicates that they are in the business of selling content, and have no vested interest in being a dedicated hardware company. They have shown a desire to be platform independent. To fail to release an ATV app for Prime would be a 180 degree reversal of that desire.