Having been out of the web app development bubble for about seven years now, there's whole industries that work entirely in the pay-for-it-and-then-download model, and while games-as-a-service is more popular now than ever before there's still plenty of the old-school way of doing things going on.
I really like the simplicity. You can buy the thing, maybe from Steam or maybe from a DRM-free store like Humble, download it, play it. You can get a refund if you don't like it, or buy another copy and gift it to a friend if you do.
[0] - https://store.steampowered.com/app/386900/The_Cat_Machine/
[1] - https://store.steampowered.com/app/654960/The_Eldritch_Zooke...