1) In Windows at least (not sure about Mac), you can 'move' files/ folders around on a drive, but you can only 'copy' information from one drive to another. Hence the files/ folders are copied to the source, but not removed from destination.
2) In the Library module, on the left panel, right-click on the folder you want to promote and select 'Update Folder Location', then point to where you want to move it.
Mike.