She did it

Apple Store employees must daily "wipe" all devices. This isn't just a physical cleaning, they are supposed to wipe the histories and fully restore the devices to "factory" settings. It's pretty harmless fun to do sinsthing like this since the device is supposed to be "wiped" end of day anyway. However employees will often start this process close to closing but while the store is still open to allow them to leave on time. You may see this going on if you go to an Apple Store late. If you do something like this once the devices have been cleaned they must do the entire procedure over. To be courteous it's probably best to do this long before closing, and not touch the devices if you see they've been cleaned up. Apple employees move stores often and in my experience remember people, so if courtesy isn't a good reason you never know when you'll need service from that employee who had to fix up after you, and if they could do a "little extra" to help you they may remember you when you do.