No. You don't get it.

Stadia just had to REFUND those games and service fees to people, because the users couldn't use those games anywhere else. It was only for use...on Stadia. And the selection was piss poor. :P

Do you see the problem now?

Why would anyone buy a game to play just on their cloud service? Either you own the game or you do not. Stadia should have partnered with Steam or Xbox or PS etc.

Or included the games as part of their subscription, as Xbox Cloud Gaming does. You can then play these games on your PC or console or on the cloud. It then becomes an option, to be used based on the device you have on hand.