A Little Thank You will do...............

Most of us are pretty considerate. Most of us will hold the car door open for someone or hold an elevator door open for some and even hold any kind of a door open for another person.  Even yours truly will always hold the door open for anyone that is behind me.  I certainly appreciate it when someone does it for me, and will always acknowledge it by simply saying "Thanks", or "Thank You", or "Thanks a lot".  It comes out of my mouth so very easy and I even usually crack a little smile while saying Thanks...........
     But............Why are there so many miserable fucken people that will not say "Thank You" in any way shape or form when I do it for them ????? Why is it so difficult for them ?  Are they so caught up with themselves that it is beneath them to say Thanks ?  Do they think I am their slave or servant merely performing my job ?  Do they just not give a shit about the rest of the world ?  I really despise these people.  Usually I just smile at them and nicely say " Your Welcome ".  That usually gets them and they will blurt out a muffled Thanks........What happened to Mr. Manners ?  Where did he go ?  Boy do I miss him.
      By the way......I wish I knew in advance what people would not say thank you.... Surely I would do something to piss them off..........LIKE........

      You get the idea.