People CAN be that dumb - a colleague at a branch of my employer once asked a customer to send in a copy of the disk which they said was faulty and wouldn't work in their computer. In the post a few days later she received a photocopied image of the floppy disk...
Years ago in my job here, we used to use real 'floppies' - the old 5 1/4" floppy disks. The number of people who'd update the program on the disk with their monthly pension contributions and then staple the disk to the correspondence was staggering. None of them could understand that driving a staple through the disk surface would make it unreadable and they'd have to do it all over again.
The best were the ones who couldn't work out how to put the 3.5" disks back in the boxes. The outer box was open at both ends so you could slide the inner-tray in with the disk in it. The inner was a long, rectangular piece of card lined with bubblewrap, which you'd put the disk in and then bend the ends up over the disk and slide it into the outer. People could never work out that if you put the inner in side-on, it was open at the sides and the disk would slide out. You had to put it in the other way so the folded-up ends outwards. They'd go to hugely extravagant lengths to wrap miles of tape around the whole thing to stop the disk falling it. No common sense whatsoever - you'd have though that seeing the disk arrive in the box correctly each month would have let them see how it was supposed to be done, but no....