Imagine a world in which most middle-class families have a cloud VM where they run server-side stuff (Mom's blog, Junior's minecraft server, etc), and when a software vendor sells you software with a client/server model, it's normal for them to deliver the server component as a container to run on your server.

That's the world in which you can buy the software you described without SaaS. As long as the vendor is running the server side, you're paying by the month.