Webnovel sites in Korea and China sell books one chapter at a time, and some of their publishers are trying to break into the Western market with the same structure (ie Wattpad bought by naver, Webnovel.com owned by Qidian). They also like using virtual currency for buying chapters. Korean and Chinese web comics are also sold this way. Publishers really like the microtransaction money no matter the industry. If they could figure out how to sell microtransactions for movies I bet they would do it.

Side note: I downloaded this chinese app for downloading region locked games on mobile and they somehow figured out how to put gacha in it. Publishers seem to do anything for money no matter how little sense it makes.