I'm a customer. These are things they need to be discussing with close friends and family. I don't want our interactions to be robotic, but I think the etiquette calls for casual, superficial conversation.
As much as I enjoy the conversations I have, I would not enjoy discussing health issues or "how much I hate this job". Yes, there needs to be boundaries on topics.
Success is to be measured not so much by the position that one has reached in life as by the obstacles which he has overcome. - Booker T. Washington