The paid Itch.io version does include the full base game. It is essentially the public version of the game with all paid mods included and no Patron Code required.
A subscription is only required if you want access to Early Access or the Dev Build, meaning newer content before it reaches the public/Itch.io release. You do not need to keep a subscription to get the "full game."
The differences between all versions are described here: https://wiki.kunoichi-trainer.ninja/version-differences the Itch.io version is updated together with the public release, while subscribers get new updates earlier.
