If there was one thing my parents taught me as a youngster, which has stuck with me my entire life, is that manners cost nothing. A simple ‘please’ or a ‘thank you’ takes no effort. A courteous ‘hello’ to your neighbours or colleagues. Or why not go that little bit further and greet a complete stranger who just either accidentally or on purpose made eye contact with you.
We are all mere humans, or mammals if you will, simply making our way through this earth, doing the best for ourselves and our loved ones. Sometimes the journey is smooth sailing, but more often it can be tough.
I see manners as a reflection of the person, a window into their soul, and can almost immediately lose respect for somebody based on the manners they use. It is wishful thinking of me to expect each person of this world to be polite to others at all times. That is why when somebody nudges me out-of-the-way to get into the train, or nearly sends me tumbling as they whizz past me on the stairs, I swallow my annoyance. Who am I to know what is going through this persons mind. Perhaps some hardship has befallen them. At that time, I am no more than a mere object.
However, when I am serving you in a store, please do not be rude. When I am an old lady being crushed in a crowd, please offer me your seat. When I am trying to assist you as a colleague, please be thankful for my dedication. After all, in the long run, good manners will open more doors to you than education, wealth and power ever can.
Joyful Antidotes 
I really wish everyone was polite, but like you said – wishful thinking!! I really agree with you that manners don’t cost a thing and really can open doors for you. I feel like people are not used to it so when you are polite they value and appreciate you more!
Yes I think so too. I love to see firstly the look of shock and then appreciation when you simply say thank you to a person or hold the door open for them.