Why was Edla happy to see the gift left by the peddler?

When Edla opened the package of the gift left by the peddler she felt very happy. She found a small rattrap with three wrinkled ten kronor notes and a letter addressed to her. He had left the thirty kroner for its rightful owner. He was not a thief but his situations made him do so. She was happy to see that he had changed himself and realized his mistake.