Vistors to our website can fill out a form to create an account. It is a CiviCRM profile, and "WordPress user account registration option" is set to "Account creation required". The username and password fields are shown above the profile but a Wordpress account is not created when the form is saved. A Contact is created, but it is linked to the Wordpress admin account (ID #1).
I attempted to replicate this on the Wordpress Demo site. I created a profile that required Wordpress registration, but it (quite reasonably) would not allow me, as the demo user, to create a page for embedding it. When I view the profile in "Create Mode", it does not show the username and password fields (even when not logged in), and no new contact or account is created.