A service like this is almost like a specialty kitchen item. My fiancée is a stickler for this stuff and it is something I really love about her. She hates speciality, single-use items. Take the cherry-pitter[1]. It's obnoxiously large, like a beefy can opener, and the only thing it does is remove pits from cherries (and, apparently Olives). She doesn't want stuff like that in our kitchen, and I don't blame her.
Regardless of your cultural background, why might you want to buy a standalone TV/streaming package for one vertical of content? I think we'd all agree the future would might involve a-la cart purchases like this... but we aren't there yet. Once you combine your Basic TV via Sling or Playstation Vue, Netflix for the riff-raff, and an add-on luxury package like HBO GO - you don't have any more room for speciality items. They need to be REALLY special in order to work. Just like the cherry pitter – there just isn't any room left in my drawers for a single purpose item.
[1] https://www.oxo.com/products/preparing/fruit-vegetable-tools...