Mormonism/LDS in its various guises is a seriously revised version of Christianity. They claim that it is the “restored gospel”. Their doctrine is at serious variance with historical Christianity in multiple significant areas. They believe that the historical churches left the true path a God sent messengers to correct things. At a macro level, their approach is quite defensible theologically. It would make things simpler for some if they declared themselves a separate religion, but their claim of Christianity is not without some basis, though it is clearly not historical Christianity.
As for it being strange, talk to some serious Mormons who were raised in their faith. They kind of get how the Roman Catholic church operates, but Protestants are beyond comprehension. It just depends on what you were brought up with. When it comes to weird, LDS followers are not all that different than historical Christianity when compared to some of the other religions out there.
LDS is no less respectable to me that other religions including historical Christianity. I respect (within some limits) the rights of others to believe and worship as they please. The practical values of the LDS community are OK by me, even if I don’t agree with them theologically. While I am a fundamentalist Christian, my political support and vote does not hinge on someone’s religion, but their policies and behavior.
we're not talking about whether Mormons are good people or not though...many of them are, and many are not...just like the rest of us...
but no matter what kind of tolerance one has, its hard to understand the very odd things that Mormonism supports....