We all get stuck at the supermarket checkout from time to time when the assistant can’t get an item’s bar code to scan. We’re left watching in awkward silence as the flustered employee waves the item every which way, upside down, back and forth, at an angle, until they’re left literally rubbing it on the scanner in the vain hope that the machine will do us all a favor, recognize that it’s a loaf of bread and beep.