The type of house "hoarder" that is unethical is in the minority.

What about those that have alts with which they play on as well and they want another house for that different persona? Remember SE makes it possible to have other characters on a server via extra payment. We hear people talking about greed of those that own multiple houses....where were these same people talking when there were plots open on all servers except the most populated? They certainly were not buying any of those empty plots.

This whole issue of greed or ethics never came up until these people decided having a house was cool and they now wanted one, in many cases these same people had other opportunities before this to purchase. What I see here is an awful lot of envy. Envy tends to lead to greed and avarice. I want what you have, I can't have it so that makes you greedy and unethical.