Sitecore Commerce 7.5, powered by Commerce Server and Commerce Server 11.1 leverages the graphical Sitecore Security Tools, which make it much easier to define and maintain custom security roles.
There are no extremely granular roles out of the box, since those edge cases can be easily implemented. Standard or custom Sitecore roles must be used to control Business User’s access to other content. All roles are in the Sitecore domain. Unless otherwise stated, all access rights are granted when using the Sitecore master database.