Lady with cookies

This very poor old lady sold super tasty cookies at Pho Quoc market. One day we noticed her and bought some cookies. She was so wondered but so happy that we decided to come and bought some cookies occasionally. Sometime She had no money for change and looked very sad when thought that we could go away. Personally I think that 1$ for cookies was all she spent for food.

However as lot of Vietnamese she always smiled to us. It's pretty good to present happiness just for one dollar, what do you think? How much does cost your happiness?