The unscrupulous ones are pretty obvious (even though they don't seem to realize it), but as with anything, their tactics must work on enough of the population to make being a dbag worth their while.
Vendors Who Post
There are a number of vendors who post to Audiogon discussion threads. I think we can fairly assume that all of them have disclosed that there are in fact vendors and are not hiding this important fact. In my experience, most vendors are very helpful here and do not attempt to primarily use the threads as a marketing tool to solicit customers. They use the threads to give useful information pertaining to their products, to clear up misunderstandings about their products and to correct misperceptions about their products. Most vendors post in a professional way with an appropriate tone. But, alas, there are some vendors who are less professional than others on these forums, in my opinion. How do you feel about the vendors who post here?