A little old lady sold pretzels on a street corner for 50 cents each. Every day a young man would leave his office building at lunch time; as he passed her pretzel stand, he would leave her two quarters, but never would take a pretzel.
This went on for more than five years. The two of them never spoke.
One day as the man passed the old lady's pretzel stand and left his quarters as usual, the pretzel woman spoke to him: "Sir, I appreciate your business. You are a good customer, but I have to tell you the pretzel price has increased to 75 cents."