Checkbox state from checkout shown in subscriptions

At least in Test mode, I can only find my custom fields in payments, not in the subscriptions. That doesn’t make any sense in my opinion, as the checkbox states are collected during checkout. Checkout creates a subscription/order and payment, but later payments of that subscriptions have no chance to show the custom fields to the user.

Use case: I would like to gather agreement to my TOS (+ other legal things) in the checkout and have Creem store the user decisions. I know I could listen to web-hook events, but if possible, I would like to manage without a backend.