Rude behavior on the road

I have been on the road now for 12 days. All together, I have pulled over about 20 times to let the car behind me pass. Of all those times, only one person raised his hand to thank me. The others just went by. Sometimes I wish I could just go back ahead of the people who did not thank me, and then slow down to show them that they should be polite. In most cases I was going the speed limit or faster. I don’t get upset about this rude behavior — not really, really upset, that is. But it bothers me. If someone pulls over to let you by, please raise your hand to thank them or blink your lights if it’s dark. It’s a very good thing to do and takes almost no effort.