Well I said I was just joking, didnt I? But anyway beauty is in the eye of beholder, so you cant be that sure. XD
Theoretically you do not have to, but it is a good practice to disable forum registration if users accounts are automatically created from adoptables sites. For an active site, you may have problems if a user registers on the site with a username already used by someone else from the forum, who is not a member from the site.
