The repercussions can affect all Classic Era realms: the players receiving the exploited goods subvert their own realms’ economies and damage the chances for legitimate play to occur on the non-Xfer destinations.
Increased competition for resources is the natural impetus for players to not roll on a densely-populated realm. Once it reaches a threshold, player populations migrate to a new equilibrium. The players exploiting these sustained, unlimited, free transfers abolish that impetus and in doing so damage the Classic Era community as a whole.