I don't speak for the board administration at all, but IMO, having a thread like that opens up potential liability.
"The reviews thread said that stormtrooperguy was great, but it took him 3 months to send me my gauntlets" would happen in a matter of... oh... 3 months.
Right now the board basically says "buy at your own risk. your problem not ours". Any involvement beyond that would imply some degree of oversight. Or couple imply it, should someone try to push the point.