Not many now who understand the needs of acknowledging, appreciating and thanking others.
For just a simple courtesy, nonetheless, it seems to be very tough and complicated to do so. And it is odd to realise that some people are very good at acknowledging, appreciating and thanking others yet never know and bother to acknowledge, appreciate and thank their family members, parents, siblings and relatives. They do not see what friends can't do and what family can do.
Some would say; blame the parents as parents are the first contact to shape their children's characters and behaviours. However, some would say; parents can't be blamed as children grow old, they have their own perception about life and they have their own concept about understanding life and understanding themselves. These groups of grown up children may have the ideas that they know better than their old parents who never get a chance to reach University or even to a college. And these children also may have some arguments with the parents about 'who knows more'.
That is reality. If you are good, do not aspect others are good too or for some reasons are better than you. There are many excellent, successful and helpful humans out there who fail to see the importance of acknowledging, appreciating and thanking others and their family members.
This attitude does not have to be taught but we, people, have to go back to the route and culture so that we realise where we begin. Hence, realise who and what we were before.