People are people. Despite being labeled as moronic cult leaders who based their existence on the possibility that an extraterrestrial might sweep them up in a UFO and take them to the next level, these people died and the masses seem to be missing the point as to what motivated them. It's not so deviant to think that a group of people sacrificed earthly desires in hopes of attaining a better world and a better way of life after they left this world. Most of the Western religions seem to be loosely based on that basic premise. What's deviant about the Santa Fe group is that they chose to kill themselves.
Most Western religions regard such a practice as contrary to gaining eternal life and happiness.
Anyone who secludes themselves from the daily interactions of life has a problem. And anyone who believes that UFOs are coming to earth to swoop them into a new existence definitely has a mental condition. But the same could be said about anyone who believes in organized religion. There deaths should be mind boggling, puzzling and worthy of inspiring people to want to learn more about these types of people. I'd hate to think that if I got wrapped up in some group and let them control my life to the point where I lost all sense of reality, that after I died people were cracking jokes about my death.