There exists an interesting relationship between the board and the agencies or indies that advertise on the board.
The agencies and indies support the bard with their advertising dollar. In return they are granted certain privileges, non-paying agencies or providers are quickly removed, the agencies generate business not only from their ads and participation but from reviews as well. BTW the agencies do not pay a premium for the reviews to the board.
The question that has to be answered is what do the agencies give back?
In other niche markets reciprocal relationships exist between the board and outside advertisers in the form of reciprocal links. Some of the European sex trade venues feature such exchanges on their front page -
lists at least 10 pages of "Friendly Sites" on their home page dedicated to link exchange.
A informal check of over 20 agencies and indies websites did not show any links back to Merb, however some had reviews posted that looked very familiar.
Another interesting phenomena is that of competition. The green board does not carry advertising or links for the blue board and vice versa, yet agencies with boards are allowed to advertise here, effectively taking traffic away from Merb.
In the retail / wholesale world such activity would rarely be tolerated. A retailer who starts to wholesale product in competition with the wholesalers who service his outlets would rarely be serviced by the same wholesalers.