Personally, I've never heard of such a thing.
For the domains (e.g. abcxyz.com) that I have, the hosting service allows me to set up email accounts (e.g. [email protected]) which can be forwarded (redirected?) to any other email address that I nominate (e.g. [email protected]).
By default the email accounts "belonging" to the domains (e.g. abcxyz.com) will only forward emails specifically addressed to the full email address of THOSE accounts (e.g. [email protected]).
I am also provided with the option (by the domain hoster) to set these accounts to be catch-alls. In this case [email protected] will get forwarded.