Some people believe that something works only if it has studies proving that it works. For someone to go and find out for himself whether or not something has practical value and ignore the so-called experts (who often act as if they can divine truth without actually testing a hypothesis -- real scientists, this lot) really annoys some people, who are themselves firm believers in the pharmaceutical-sponsored version of medical reality.
And then these people, who clearly have nothing better to do with their lives, spend hour after hour surfing CureZone (a site dedicated to exploring the alternatives) decrying those alternatives and those who promote them.