I can't think of any reading off the top of my head, but Patreon and other services usually work this way: many creators provide their primary work (the web comic, the podcast, etc.) for free, regardless of backing. Backers typically get extras. For example: I received a digital sketch of my choice for backing a comic artist.

Look-up Patreon.com. It works by people opting to either donate money for a specific project, a certain amount of money a month, or a certain amount of money per article/comic/video etc.

There are no paywalls, it is like a wealthy patron paying for a public concert.