I'm sorry buddy, but it is a matter of morality when you're telling other players that what they are doing is against the rules when its not. Go ahead, read the list of prohibited activities. Read the terms of services. You won't find a single mention of housing.
How am I not any better? Last I checked, I'm not the one that is trying to tell other players what they should or shouldn't do in a video game. If you can't wrap your head around that concept, you're a lost cause.
Using RMT for housing transactions is heavily discouraged by the housing community so I don't know what the hell you're ranting on about. If it wasn't clear already, GMs will not assist you if an issue arises and you didn't pay with gil.