I'm trying to manually register a participant for a specific event, but the registration form is showing custom profiles that I've created for completely unrelated events. I'm unable to complete the manual registration until I've made a selection for all these required fields. This particular event does not use the profiles being show or show these profile questions on the public registration page, they only appear in the manual event registration page, below the Registration Confirmation and Receipt section. I don't see any mention of this in the manual (https://docs.civicrm.org/user/en/latest/events/manual-event-registration/), which makes me wonder if it's a bug.
How are these profiles getting here and how can I get rid of them without completely deleting them from my database?
I'm running CiviCRM 5.8.2 on Drupal.