Yes, it needs to be installed on at least one machine for Revit & Civil 3D. It's a small install file, less than 10MB. Maybe less than 5MB.
Just to be clear, the Shared Reference Point tool is not a viewer - it's an add-in for Revit/Civil 3D. Are you referring to the Navisworks Freedom viewer? Someone will still need to compile the RVT/DWG/NWC files into an NWD file to be able to view in Freedom.