Service in America

I was surprised at the service in America. In America, when I bring clothes to the counter in the shop,the clerk smiles at me and says, "Hi, how are you?". It is so friendly and starts conversation with clerks. First, I was confused about this action because I have not experienced it in Japan. Japanese clerks say, "Welcome." and tell me the total price, so we do not have conversation. Of course I like American's service better than Japanese's service because American's service makes me feel comfortable and happy.