The User is considered as Cardholder/Proxy Pan. User is only considered for Transaction purpose, and is not intended to perform any admin activities in the RA admin console.
Hence, we should ideally not be creating User's and instead we should always create Admin ID's and provide the required privileges, using the Roles.
Note: The create user option was available in RS version 5.5 ad below. The latest versions of RA admin console don’t have the create User option.