I have done 15 years of retail. Standing is worse than constantly moving. We in the USA are insane by forcing our cashiers to stand without having a chair to use for those 4, 6, or 8 hour shifts. The perception is you are not working if you are sitting.
Does anyone know of any place that lets their cashiers sit? My only recollection is the old style cafeteria w/ the register and stool at the end of the tray line.