The zip files on itch.io are compiled already! Just download and play!

Actually, the link in your parent comment is a freely available playable binary. You don't need to build it yourself. The only different with steam version is you need to update it yourself because it does not include an auto updater (Steam one neither, but steam itself is).

The only platform you need to pay to play is ios. Because… Apple tex. You need an expensive mac and yearly paid dev account just to submit anything to appstore. It's not reasonable to ask anyone do it for free (let alone time consumed on maintenance)