Here's the situation:
Let's say that person A is offering an article writing service in the Warrior Classified Ads section. Person B will be a competitor, offering a similar type of service at a lower price. Now, a potential customer, person C, (or even current customer) posts on person A's thread inquiring/reviewing about the service. Person B notices this thread and the comment/question made by person C.
So here's the question:
Is it "right" for person B to contact person C via pm to notify him/her about the cheaper service that he is offering?
Or, is it person B's responsibility to get his thread and business noticed by potential customers?
When I was in the situation of person B, I have always thought about contacting person C. However, I have never acted upon those thoughts.