I believe that many indie developers are not using Itch.IO to the fullest. This means having a full lengthy description, screenshots, and even a game trailer. This is the way you allow yourself to practice for bigger and bolder games that you are making for retail. Without treating these demos, prototypes, and mini-games like a full release you miss an opportunity to gain a new fan. That completely defeats the point of creating your projects. 

I truly believe that once you start taking these Itch.IO projects like full releases, then you start to train yourself to reach more potential fans. Plus you gain the knowledge to reach and target your branding and marketing effort to convert more players to future fans. This is why you must continue training yourself with every project post.