You may have about the massive "checkout outage" that hit tons of Target stores over the weekend.
This must be related to that. A guy at a Target store in Texas shot video of shoppers and their carts on Saturday, and they're lined up from the back of the store to the front.
It takes him about 45 seconds of walking past everyone waiting in line before he gets to the cash registers . . . and you never see one cart move forward.