[drcy]

No doubt lots can be shilled without consignors' knowledge. The auction houses get a percentage of the final bids and would like all boats to rise, and some outside collectors like their investments to maintain their market value. Some collectors are willing to buy cards just to 'protect' the market value of the copies they already own. Of course there's nothing errant with honestly (I said honestly, as opposed to a miscalculated shillingly) buying the cards, other than it may be seen as a dubious investment strategy.