A full name is sure helpful when you're trying to find a user who signed
up with an ID like [log in to unmask] and is sending you mail from
[log in to unmask] raising six kinds of hell because he can't unsubscribe
(and refuses to tell you or doesn't know his original signup ID).  You
can apply the same thing to Compu$erve addresses of course, or for that
matter to any address that doesn't map well to the subscriber's name.
Is [log in to unmask] James A. Dixon or John A. Doe?  Only their hairdressers
(and ISP) know for sure.  Requiring a full name is one way to help you
figure that out later.

Nathan