Well, there is an inherent worldview difference between "the bottom line is profit", and "do not store up for yourselves treasures on earth", but leave that to one side. The ethical questions of placebo effect are certainly important, but given the lack of knowledge of how conventional treatments for back pain work, and the fact that many explanations have had to be revised in the light of greater understanding of the complex physiology,"not knowing how it works" doesn't seem to be the overriding issue in many cases, so much as a vague idea that the drug-receptor model (for example) is "OK", whereas sugar pills having as great an effect is "woo". And therefore the standards of evidence are applied differently.
But given the known genuine benefits of placebo, the current medical ethic of explaining everything, including the failure rates of treatment, even if it jeopardizes recovery, could be seen as a little odd. Though in one fascinating example I saw a physician explained to his patients carefully that he was going to use a placebo for their condition, and still got good results - I've forgotten the condition, but it was a clearly physical one.
Acupuncture was available from one of my friendly pain consultants when I ran a back clinic. My own impression of its results overall wasn't that great, but that was one practitioner in one condition. To counter Phil's general (and frequently made) charge about placebo effect in relation to paying a sympathetic practioner, I can say that those it did help had it administered by the same friendly practioners who had usually already tested the placebo effect of drugs, injections, physiotherapy and so on - and only the placebo effect of the acupuncture helped. So the placebo effect appears to be as detail specific as individual drug treatments.
Beyond that, I endorse Richard Wright's skepticism about the results, and perhaps even the good faith, of many studies on such things, and endorse beaglelady's testimony. I myself was only needled one as a demonstration by an acupuncturist on a back pain course I was running.
I gained my own interest in back pain when I did a course in spinal manipulation early in my GP career, partly from the feeling that I was only trained as a delivery system for drug companies, and would be utterly useless to people if I were stranded on a desert island.
Learning to use my hands diagnostically and therapeutically changed the lives of literally thousands of my patients over three decades, and the more I was able to refine and target its use, the more effective it became, including sharpening up my diagnosis of serious conditions missed by others. Since it was not regarded as a proper medical treatment, it's the one thing I've occasionally offered to friends and family since I retired, and has won me a good number of pints of ale amongst musicians restored, to their surprise, to comfortable playing.
And yet the journals carried a regular stream of articles claiming it was shown to be no better than placebo, and so on. In most cases one could work out the design errors of the trials, but it often boiled down to the researchers setting out to demonstrate the inefficacy of something outside their own model - which is where I came in with my friend the heart patient (to whom I could have added maybe half a dozen other instances in my experience, including those who accepted prayer utterly convinced it would not help).
Incidentally, my hypothetical understanding of how manipulation works shifted over the years, a paradigm shift occurring when I started to work with experts in the physiology of chronic pain. At no stage did I resort to "Goddidit" as the default explanation, though at every stage I gave him as much thanks as I did for my daily bread.