In the English-speaking Caribbean we call them "Peddlers."
Those who work extra hard, and with notable dedication and diligence, for a cause, issue or individual, we call "Peddlers" for so and so. Or "Peddlers" for such and such a thing.
And that is fine.
But what is truly amazing is that no one seems to ask who in this world is really NOT "Peddling" for something or someone. For, it seems in this world everyone is peddling something -- or for someone.
So, the question really is not whether or not we are peddlers, but who is peddling for whom or for what.
Keeping this whole thing a secret has to be one of the most cunning strategies of Shaitaan.