As a member of the Church of Jesus Christ of Latter-Day Saints, I feel the opinions on this thread are not well informed. We believe in the Book of Mormon: Another Testament of Jesus Christ, but we're not "the Mormon church." Although it's no longer PC to call our members "Mormons," so many do that we just tolerate it.
I think we get along very well with the Amish; in fact, despite differences in doctrine, there are some locations in America where Amish and Latter-Day Saints hold joint church services, out of mutual respect.
The Church teaches that the "law of the land" should be obeyed, so we generally oppose any crime or gang activity, and we support local governments whose job it is to support the laws and protect its citizens. Members who grew up in LDS families can decide to quit attending church or even ask to have their names removed from church membership records. This is not a crime or considered taboo, and there is no punishment. Those who depart from the Church's teachings are no more likely to develop mental illness than any other segment of the populace (which has been researched).
Although I'm not authorized to speak on behalf of the Church, my wife and I are currently serving a mission in the Philippines. Our mission is to invite all people to come unto Jesus Christ and gain Eternal Life through faith in Him and His Atonement.