The common sense part is so true, but it sounds more like Mark Twain. I don't do something for someone for something in return, I was not brought up that way. It is just like Eddie said. And yes it does make it nicer to at least hear or see a thank you, but the lack of it should not deter you from being courteous, or kind. I once got into a wolf discussion with a woman who was instrumental in getting wolves restocked in Yellowstone. I was courteous, and eased in my comments, in a polite way. She responded with, "why is it that you want to keep the hunting of wolves intact, but I find it hard to dislike, or be upset with you ?" Could be I was courteous, and listened to her reasons, and then answered with mine, while not calling her an airhead who needed to see first hand what she and the others have done, and keeping a pleasant tone of voice, and added that I did not want to eliminate the wolf, but keep it's population in check, so that the damage that the wolves are doing will be lessened. Unfortunately common sense manners are no longer taught in the family anymore like it once was. A Friend of mine was a teacher, and he was at a PTA meeting one night, and one nit wit parent stood up and wanted to know why the school was not teaching the kids manners. He responded, that it was the job of the teacher to teach the basics of reading, writing, and mathematics, and social studies, and science, not manners, that is the job of the parent not the teacher, parents are responsible for teaching common sense manners and courtesies, mostly by example. Wasn't the answer they were looking for.
Wayne