stirringleaf, first, in Judaism you do not not not not not need any 'intermediaries.' Oy vey, no. That is entirely *not* a Jewish concept.
A rabbi is simply someone who is well-trained and educated in the intricacies of Jewish law and lore. THAT'S ALL.
In Judaism you also don't need a "minister" to marry. You need witnesses. And in some Orthodox communities seemingly most of the men are rabbis just because they've had the requisite education just as a matter of course. And all those people who also happen to be rabbis are also English teachers, doctors, lawyers, accountants, plumbers, auto mechanics, bakers ... etc., etc. ... The rabbinate is a poor way to make a living in the Orthodox community, as there are few who can actually make a living running a synagogue or doing all that "pulpit" stuff.
In the liberal denominations (Conservative, Reform, Reconstructionist) the concept of the rabbinate is a little different, more along the lines of clergy required to "perform" (read: coordinate, or officiate at) this, that and the other lifecycle event, etc.
That said ... long ago, before becoming Orthodox, I planned on going to rabbinical school. And why get ordained? I could have just gotten the education and know a lot about Jewish law and lore and that would be that. However, the actual ordination would have been a career choice. Getting a title for the purpose of making a living with it. And grooving on the title itself, of course. To be honest, the grooving-on-the-title thing to me was huuuuugggge.
And that's not to say that all who get the title are doing it for economic reasons or self-aggrandizement. No offense intended.
Not entirely sure how that translates into your question ... but that's my experience.