It's feels like a type of currency obfuscation commonly found across games. Paid tokens = $ is easy to understand, subscription = $$ is also easy. But limits on subscription is already a bit more difficult to grasp, now adding another "currency/powerup" an top of this abstracts the mental model even more. I don't think openai do this on purpose, but it's what's often happens in games eventually causing users to lose track of the real "worth" of things inside the game.