Sure, but it's needed if you have multiple users|mailboxes on the domain and you don't want to manually create the rules to forward mails for another users for

Sure, but it's needed if you have multiple users|mailboxes on the domain and you don't want to manually create the rules to forward mails for another users for each alias you|they had used. Because I'm the only user on the domain I don't need the subdomain addressing.