As far as your stance that we should be weeding people out for various practices - this has been addressed many times over. First and foremost, we are not going to serve as judge and jury on such matters. What is brought to the BOI is often one sided; and, if it isn't, the two sides frequently give different accounts of what happened. You want people with no intimate knowledge of the situation to take one person's side, and remove another person from this site? How many times have we seen questionable, petty, or flat out fabricated complaints brought against a seller (or buyer)? How many BOI posts are essentially one hit wonders - in which a buyer comes in & blasts somebody over some slight (real or perceived), but leaves out the fact that they were fully compensated by the seller...or the buyer fails to come back and update when the situation has been resolved?
Besides, us taking the stance that we will remove anybody shown not to have acceptable business practices would lead to an expectation that anybody advertising here is safe to deal with. Sorry, but a seller's reputation is only as good as his last documented transaction. "Good Guys" can screw people over, "Bad Guys" can provide healthy animals and acceptable customer service....heck, known "Bad Guys" can make good on problems, turn over a new leaf, and become "Good Guys" - it's happened. What are we to do in that case? What would be the process for reinstating somebody? Does making good on a particular transaction mean that the person won't screw up again? By the same token, does a person with an extensive (positive) history deserve to be banned because he feels an issue is not his fault & refuses to yield to the demands of a customer?
As far as the undercutting, sure, SOME scammers use the too good to be true pricing; but not all of them. If you want to talk about the economics and market pricing, there is a thread in the BP forum that includes a few "articles" by Colin Weaver (it should be required reading, lol).
http://www.faunaclassifieds.com/forums/showthread.php?t=278912