Two reasons behind this topic. No.1, it has got to do something with their family education. As is known to all, people have to show their respect to the ones they work or study with. We need to do so mainly because our parents used to tell us how to behave in the public. They are doing right, undoubtedly. No.2, it is a proper way to show basic manners in front of those people who we dislike. The manners you know, it is a part of our traditional culture and it has been with us for thousands of years in my country. So, this is why we could be friendly with people we don't like. That is it.