I noticed years ago that the American Heritage Dictionary does not list the etymology of the word, "hobo." There is just a question mark for the etymology. A guest of the Johnny Carson show once said that the word "hobo" derived from the words, "hoe boy," to refer to migrant farm workers (many of whom carried a hoe, a farm implement) during the economic period in the United States that was called The Great Depression. He said that the distinction between a beggar and hobo is that a beggar will just ask you for money, but a hobo will work for it.