If someone wants to take advantage of it and it provides them with something, then it's all good.
No, it's not. Sometimes it leads to real harm.
(Not unlike how Mr. Jobs pursued "alternative" treatments for his cancer at first, instead of just going with conventional "real" treatments. Who knows what might have happened if he didn't waste that time?).
I note that you mentioned "if they are doing it as some sort of a cure for something or as some sort of a medical thing, that's one thing, if they are doing it along the lines of massages and just general working out in a gym, then it's not really that much different."
But that is exactly what acupuncture is advertised as, a medical treatment. Relaxation has real benefits - but people usually don't get acupuncture just to relax. Pretending an ineffective treatment is effective is ultimately harmful. Even if you aren't using it to treat a serious illness, it legitimizes the quack treatment for others that may be in a more dire situation. It's just plain stupid.
http://whatstheharm.net/acupuncture.html