As of now, when you unlock an archpath, youre only allowed to claim rewards you havent claimed yet. Which means if you claimed your free rewards and then go back and purchase a key to unlock it, you wont get the unlocked reward because that day has already been claimed. This seems anti consumer, and unfair considering there isnt a warning or disclaimer before unlocking the path.
Ive heard this is to prevent "double dipping". I ask the question, "whats wrong with that?". If the free rewards are free anyways, what does it matter if we get them with the paid items as well? When compared to other games, there are free rewards, and premium rewards. All of which can be claimed when the premium pass is purchased.