I actually find student sections dressing as missionaries both inoffensive and hilarious. It's unique to our school, it's not mocking anyone, and it's fun for them. Have at it. It isn't, say, Stanford's marching band doing a polygamy-themed halftime show, or another fanbase drinking jello shots.
I really, really appreciate the author's pointing out the double standard of mocking Mormons while protecting other religious groups though. That kind of critical thinking is a rarity nowadays. Good for him. I actually appreciate that our school is well-known enough to encourage this kind of trolling. If we were New Mexico state they wouldn't bother.