another question :) If a user registeres on a multisite installation without registering a site/blog

Sorry a lot of questions...

If a user registers on a multisite installation without registering a site/blog can they access their profile to add shipping and billing details?

If they just register they arent added to any sites. When I log in as that user I cant access my profile page. Do I need to be linked to a site or blog to have a profile?

Is there a direct http link to the profile once I am logged in?