The categorization is The Church of Jesus Christ of Latter-day Saints. Yes, members of the Church are often known as "Mormons," but that is the nickname that a lot of people call them by. The Church says that the official term for these members is "members of The Church of Jesus Christ of Latter-day Saints."

Of course some people think that's rather long to say, so the church acknowledges that people will often call the members just "Mormons." Nevertheless, that remains as only a nickname for the church and part of the official name of one of the books of scripture, The Book of Mormon: Another Testament of Jesus Christ, because of the prophet named Mormon who abridged the original writings. The only other official names with "Mormon" in them are the book Mormon Doctrine and the Mormon Tabernacle Choir. As for members themselves, reference to them as "Mormons" remains only a nickname.

So you say that the official info box text is to leave it without nickname quotes. So what? Why shouldn't we ammend that official policy so that it makes room for that type of labeling? And so what if there is "no need" (<- those are the "you're saying it, not me; and not that I believe you" quotes right there) to change it? That doesn't mean there would be anything "wrong" (as you'd probably say) with adding them, does it? They are not errant. They are not like adding an apostrophe to a word where none belongs, in an attempt to form a plural! They are good to show outsiders the difference between the official church name and the nickname. What's so "sinister" about that? I say we change WP:Mormon's rule about it. Why not? Well, of course that would require a concensus, but why would people have to be so opposed to it?

What about the intro. of Donny Osmond? That uses quotation marks to set apart his nickname of "Donny" from his real name, Donald Clark Osmond, in the form of "Donald Clark 'Donny' Osmond." So there. Why can't the LDS church in info boxes be that same basic way (including be adjusted as WP:Mormon policy)?