Xfinity Stream is only fully functional on home networks that use Xfinity Internet

I'm probably the millionth person to discover that Xfinity Stream won't deliver programs currently being recorded by an Xfinity DVR to streaming boxes (Apple TV, Amazon Fire Stick et al.) when the streaming box is connected to Xfinity Wi-Fi. Those of us with customized Wi-Fi networks using mainstream Wi-Fi routers or semi-professional gear such as Unifi and Omada are out of luck; Xfinity judges us to be "outside the home" and therefore in violation of its license agreements with content producers. After our shows finish recording we can access them just fine from the Stream app running on mainstream streaming boxes. 

Every time somebody reports this problem to support, we get a runaround about rebooting modems we don't have and deleting and reinstalling the app. There's some mumble about registering home network devices, but nobody knows how to do that or if it will even work. 

So my question is why Xfinity doesn't make it clear to its cable TV subscribers that Xfinity Stream only works for Xfinity Internet subscribers. This would save customers thousands of hours of pointless attempts at fixing a problem that exists by design. Apparently Xfinity Stream exists to create demand for Xfinity Internet. That's fine, but why don't you tell us that in advance? 

If I'm wrong about this and the mysterious registration process will fix the problem, kindly tell me how to use said process. While you're at it, what on Earth is the rationale for requiring Wi-Fi access when Ethernet access is much better proof of location than Wi-Fi will ever be? My Apple TV boxes are wired, and my Amazon Fire Sticks are Wi-Fi connected. Both should be treated the same, and real Wi-Fi networks should be treated the same as the consumer-grade Xfi.