I don't know tons about the mormon religion. Most (if not all) of the Mormon individuals I've met have been nice, caring people. I had a friend (from church actually) who converted to Mormonism and got married. While none of his friends/family were able to go to the temple ceremony, they had a seperate service/celebration for others. I don't know what the big issue is.
Funny thing is, what most people are criticizing Mormons about are also true for most runners. We practice an unusual sport. This requires intense devotion to be considered a "runner." People who are not runners look at us and think we are crazy. People limit their relationships and lifesytles around running.
I think that in the end, whenever someone is passionate about something so much that it truly impacts/effects their life, other people are uncomfortable.