The LDS (Mormons) believe all other churches are an abomination. Is that not insulting to everyone that is not Mormon? The church started by Insulting everyone, what do you expect.
(Pearl of Great Price, Joseph Smith 2:16-19, 1977) 19. I was answered that I must join none of them, for they were all wrong; and the Personage who addressed me said that all their creeds were an abomination in his sight; that those professors were all corrupt; that: “they draw near to me with their lips, but their hearts are far from me, they teach for doctrines the commandments of men, having a form of godliness, but they deny the power thereof.” (Pearl of Great Price, Joseph Smith 2:16-19, 1977)