http://en.falundafa.org/eng/zfl_new_7.html#5James this is a good point you bring up. This question is directly addressed in Zhuan Falun in one section of the book entitled "Hospital Treatments and QiGong Treatments":
http://en.falundafa.org/eng/zfl_new_7.html#5
The argument seems to be that you have to be trained up in QiGong for it to work.
Well, why not train up everyone? Why aren't governments jumping at the chance to eliminate 70% of all human disease? Why don't they put money into making sure that everybody becomes a QiGong master?