Are opt-outs not honored when a user doesn't have a profile?

I am testing some sending and sent an email to an address not in a profile. I clicked the update preferences link in that email and opted out of all. I then sent a different email to that email address which is part of one of the opted out topics. The email was till sent to that email address.

What am I missing here, why is that address still sent to?
If a new email is sent to a profile isn’t automatically created for that email?
If this stuff is written in the docs, I am happy to read about it, but I didn’t find it.

Hey @brett :wave: - Thanks for using Courier! With Courier Preferences, a user_id has to be passed in the request. This ensures that a recipient’s specific preferences are saved and respected for future notifications. A user_id is tied to a Courier profile.

user_id, is that the same value as a profile.recipient_id?