@ludman1 Yes, the 'Invite to server' triggers the "Great Invitations" aka Easy Invites. Prosody and Snikket have that and since recently ejabberd as well.
This is exactly for small, family and friends deployments that don’t have open registrations.
I’m not exactly sure how the access control looks like on ejabberd. Maybe only the admin can trigger easy invites. I guess theoretically there are also deployments possible where all users could trigger them.
@zeank can probably tell you more.