If you are a registered user logged onto the SE network, say to UX.SE, you have a user account with reputation and badges, etc. When you go to check out another SE site (cooking.SE for instance), at this moment, you'll be treated as if you were a new user.

Do you think that a registered user should be treated as a new user when visiting another site?

Disclaimer I've posted a very clumsy question about that on MSO.