A couple times when I've been in Residence Inns I've used one or two of the dishes, rinsed them and left them in the sink to be put in the dishwasher on my last night with whatever dishes I've accumulated. Then I've returned to see the housekeeper put the one coffee cup or whatever in the dishwasher and ran it. So much for those saving water hanger signs.
another reason to leave the "Do Not Disturb" sign on the door throughout a two- or three-night stay