I have always tended to look down on chiropractors, but they will never go away as long as they are able to offer people great subjective relief from conditions that MD's refuse to treat.
When a person is experiencing chronic pain it is very easy for an MD to "solve" the problem by saying that it is psychosomatic. There often is no test that can prove the pain is real or where in the nervous system it originates. The patient doesn't return to the same doctor, so the doctor sees the problem as solved and this encourages the doctor's feeling of self-righteous justification. There is also a "party-line" in medicine which doctors must follow to be a member of the club: 1. People with chronic pain are all just malingerers 2. Chiropractors are all complete charlatans; any perceived benefit from them is entirely psychosomatic.
If we had better technologies for locating and visualizing the sources of chronic pain, MD's might be able to actually help people more and thereby get some business back from chiropractors.
I have run across some chiropractors whom I wouldn't recommend to a patient. But some D.C.s are very good healers. (A lot of chiropractors mix their traditional chiropractic stuff with acupuncture, with occasionally very impressive results.)