This app was mentioned in 5 comments, with an average of 1.20 upvotes
The developer has to build each game thinking about gamepad support (or maybe just the remote control support), making sure the game is 100% playable without touch screen. They should also make sure the game or app works on landscape mode (instead of forcing portrait mode). For some touch-heavy games, they must make sure they work fine with just a (virtual) mouse pointer.
After all of that work, they can/should enable Android TV as one of the target devices/platforms/groups.
However, unless the game is built from the ground up with multiple input methods in mind, it takes a lot of work (which means a lot of time, which means a lot of paychecks for developers) to build such features. In the end, it's a business decision: will the sales cover the costs of paying the dev team for such features? Given most Android TV devices have terrible hardware (which means most devices won't be powerful enough to run most games), this reduces even further the pool of potential buying customers.
Sidenote: I've seen many games claiming to support gamepad and Android TV that don't work correctly. Either having a useless pre-game screen that doesn't support gamepad, or having broken gamepad support (even on Steam), or claiming to support Android TV but not accepting any input method other than touch… Android TV gaming is in a dire state, near-hopeless.
[Android] (Game)
Back to Bed
https://play.google.com/store/apps/details?id=com.bedtime.backtobed