Everyone around here still says Merry Chritmas regardless of religion or belief. I always say it to whoever checks my order and I get a smile back with "Same to you and have a great day" , If someone greeets me first I do the same...somehow it seems that the more you say it the more contagious it seems to be and it puts everyone in such a good mood to be acknowledged. Some of those clerks are pretty tired at the end of the day so why not show a bit of cheer and appreciation to let them know they are thought of.