Why does the LDS church have statues of Joseph Smith if they don't believe in worshipping graven images?
While Mormons revere Joseph Smith as a great prophet and teacher (similar to Moses, Noah, etc.), they do not worship him. In addition, a statue alone does not imply worship. Around many nations, including the United States, there are statues of leaders, dignitaries, and other noteworthy people. You won't find many who worship those people, especially the statues, but many people revere them as great historical figures, and a statue becomes a reminder of their life and service.
Mormons worship God the Father and hold deep gratitude for Jesus Christ as the Savior. In the 531 pages of the Book of Mormon, references to Jesus Christ appear over 3,900 times. Joseph Smith's name appears 14 times in the front matter of the Book of Mormon, including the title page, introduction, and testimonies of Book of Mormon witnesses.