How do some professions maintain monopoly status?

Being an aspiring member of two famous professions(Chartered Accountancy and MBA-though some people may disagree on the latter), I've had occasion to compare and contrast these two to other disciplines.

Those following the Indian markets would note that a certain educational body has sought equal status with that of ICAI(the Indian accounting regulator). This post is my 2 cents(paise?) on this.

 I've noticed that intentionally or otherwise, "body of knowledge" is becoming more complex.  What do I mean by this? The curriculum studied by entrants becomes difficult, jargon filled and inaccessible to the layperson. This builds the argument that you need professionally trained, skilled and expert personnel to do the task and use these professional tools. This results in a monopoly controlled by the certifying body.

I'm not saying that profession should be a free market with any and sundry allowed to do so. All I mean is that using complex jargon and intricate mathematics is not the way forward to establish the profession. Merely impressing the layperson with one's intellectual prowess is not enough; one should establish oneself and then claim the profession tag with its monopoly privileges.