Resource Mgrs should automatically see their groups in planning view

Currently, when you go to resource load module>Groups I manage, no groups show on the screen:you still have to choose from ALL of the groups within your instance instead of automatically being shown on the screen the groups you are already designated as a Resource Manager for. Why are these extra steps necessary? What is the point of designating resource managers at the user group level when everyone with access to the resource load module has the ability to choose from all of the groups that exist in the system whether they're Resource managers of them or not?