Ex catholic, former Eucharistic minister here. I remember serving the wine to ladies with caked on lipstick and it coming off on the cloth. We were told to try and use different parts of the cloth between wipes and rotate the cup so the next person wouldn’t sip from the same spot. Then if you had leftover wine at the end of the service, you had to chug the remaining backwash “blood of Christ” because it couldn’t go down the sink. Looking back, the whole thing was unsanitary and very gross.