Thank you for saying this. I also make the effort to express appreciation to people who have shown a kindness to myself or someone else. But as a rule, it seems to annoy them. They get turned off by it somehow. It occurred to me that perhaps it was my physical appearance, because I am only 5'8" and don't speak with a deep baritone voice or because they think I am ugly or perhaps I remind them of someone else that they dislike or maybe they are just preoccupied. But after much observation, I find that even in a forum such as this one, where I am virtually invisible, I still get the same reaction.
One thing is for certain. There is something or things about me that people find repulsive. Just haven't figured it out yet.