You get to control the flow of information passing through your system for the relay runner. You can do something with that in a more intimate way that the user appreciates.
As the user, maybe I want privacy and ultra available services and you as the relay runner have the only #reticulum gateway accessible that is not included with any free service. In many cases, you could offer your relay as the identification layer to a hosted application via OpenID Connect instead of collecting toxic metadata associated with traditional registration & signup methods. The bundled streamlined communication medium reduces overhead such as smtp.