I have to say, after that service with a smile, I left the store with a bit of a spring in my step. There was the simple power of a friendly smile. There was the power of another individual showing you that you matter.
This friendliness cost the employee absolutely nothing, gained him a far more enjoyable morning, and gifted everyone he met with a lifted spirit with which to face the day. I'll bet that friendly attitude was contagious.
If you see this post, it may also be lifesaving in some instances: http://jsbrookspresents.blogspot.com/2014/07/the-power-of-smile-suicide-prevention.html