I did not mean the actual method of payment schedule. You would support a creator for something that typically would not be sold as a finished project, but support the ongoing creation of content. Webcomics. Youtube videos. Podcasts. Anything that would get posted regularly.
You could do a kickstarter for a game. But you would not do a kickstarter for a single page of a webcomic. Or a single video blog entry.
What is the content provided by making a game? The ongoing content? Of course you can still fund the creator and thus finance the game, but the notion of subscription sounds wrong, unless we are talking about server hosted games. It is a prolonged kickstarter, and the benefit is early access and maybe bonus material.
You subscribe to a service, not to a project. But you can patronize a project.
As a side note, I believe the reasons why most creators are subscription based and not per item is practical reasons in microtransactions and minimum tier. If I look at something like a daily or even biweekly webcomic, you would have 30x minimum tier. But even 8x minimum tier is a hurdle, even with minimum tier being 1 buck.