Good manners are important across the globe, but that doesn't mean they are the same all over the world. The rules of politeness vary greatly all over the world, from country to country everywhere.
Once we read the article about Marta Ingram, who was English and her Russian husband, Alexander.
When she first met Alexander and he said to her, in Russian, "Naley mne tchai — pour me some tea." She got angry and answered, "Pour it yourself." Translated into English, without a 'Could you?..' and a 'please', it sounded really rude to her. But in Russian it was fine — you don't have to add any polite words. However, when she took Alexander home to meet her parents in the UK, she had to give him an intensive course in “pleases” and “thank yous” (which he thought was completely unnecessary), and to teach him to say sorry even if someone else steps on his foot, and to smile, smile, smile.
Another thing which Alexander just couldn't understand was why people said things like, "Would you mind passing me the salt, please?" He said, "It's only the salt, for goodness sake! What do you say if you want a real favour?" He watched in amazement when at a dinner party in England they had to eat some really disgusting food and she said, "Mmm... delicious." In Russia people are much more direct. The first time Alexander's mother came to their house for dinner in Moscow, she told Marta that her soup needed some flavouring. After that when they argued about it Alexander said, "Do you prefer your guest to lie?" Alexander complained that in England he felt like a 'village idiot', because in Russia if you smile all the time people think that you are mad. In fact, this is exactly what her husband's friends thought of her the first time she went to Russia because she smiled at everyone, and translated every 'please' and 'thank you' from English into Russian.