I never said we changed tags during store hours. Our store level POS also aren't hanging tags their full shifts, I'm not sure what else we have them doing but it seems like only about half their job or less is physically hanging tags. Our stores are also a pretty good size with more individual SKUs present than most traditional grocery stores given that we're technically a "mix" store which carries both natural foods (like Whole Foods) and conventional food categories although our identity is more on the natural foods side.
POS just isn't a big cost for a grocery stores and given that grocery stores carry more SKUs than most retail businesses that then means POS isn't a major cost for most retail in general.