well, would be nice if WG presents the list of winners - 5000 people bid over 100mln where average players number is around 8k, active accounts somewhere around 30k, so really at least one out of six players have that much of silver available? On the other hand maybe they have (that amout of players (7-8k) may play the game regullary)
one way or another - WG always knew how efficiently "take money" from the players :)