Never went on a management course and never been a manager, I always say please and thankyou. It's polite. Sorry you have a chip on your shoulder about it though.
It's the same as when sales people talk to me and intersperse "Well, Mr. wink, you know about this great offer, that will benefit you, Mr. wink, very much. As I said earlier, Mr. wink." - makes me want to end the call right at the 2nd mention.
I would tell you to cut that shit out, if you dealt with me in person. I really would.