I think this is of big help when the user is to navigate trough several levels of subdirectories to find a file in let's sat : /dir1/dir2/dir3/dir4/targetfile.txt.
Sorry to say it, but in Windows Explorer it's much easier, while all folder icons are on the top of the list, while on Mac OSX and Ubuntu it's rather annoying to look alphabetically trough the icons to find where the next folder you need to go trough.