selling or buying merit is not against the rules,there will always be people who try to abuse ANY system in place
the thing is,they cannot just get away with it easily
if their posts are rubbish and they get 5-50 merits for an obviously spam post (or a "special" merit magnet topics as I call them)
the rules also do not prohibit for a D1-D2 trust member to waste their efforts by red tagging

don't know where the 28$ figure is coming from,but that is crazy
Eventually, due to effects of merit system, merit abusers, merit cheaters, merit exchangers, and merit farmers will be found; then all of them will be banned by forum moderators. With merit system, anyone in the forum can easily see the merit history of other users (both sent and received); hence strange merit movements will be found for sure. I have no doubt about the scenarios in which more and more merit farmers/ account farmers will be discovered and cleared (wipen out) of the forum. Thanks Theymos for launching such a amazing anti-spamming system.