But aside from that, collecting a minimal fee seems fair enough to me. If paying 20 cents per sale of your successful game is ruining your life, maybe consider investing in some of the open source game engines.
This seems to include re-installs, multiple devices, new computers. I wouldn't have batted an eye at 20 cents per sale. Per _install_ is catastrophic.
Charging a flat fee per installation, even for games that have already been developed and released (many of them for free), is insane.
Above all, a single player/user redownloading the game on their device counts as a separate install. They've now said that they're using proprietary "fraud detection" and IP address uniqueness to prevent fraud, and seemingly requiring devs to reach out if they think they've been overcharged.
A fixed fee like that also effectively kills popular $1 games.