iTunes Media folder issue - files greyed out in iTunes Media folder

So for many years, I have been ripping my DVDs using software and then added them to my iTunes via the "Automatically add to iTunes" folder non my iTunes Media. Then I use finder to locate those files in the iTunes Media folder ie: TV Shows folder or Movie Folder and I copy the files and paste them onto an external hard drive just as a backup. In the last two days I have ripped some DVDs, added them to iTunes as usual but when I go into finder to navigate to them in the iTunes media folder some of them are greyed out. When I try to copy and paste them it says they can't be copied because they are in use. The media plays fine in then iTunes player and on my Apple TV using Home Sharing so I am wondering why they are all of sudden greyed out and not letting me copy them. Any ideas?