How does making the blood BoA let you buy a full set of gear with gold from tokens? Don't you still have to uh... play your alts to mail the bloods across your account?
Moreover, how does making them BoP stop this, exactly? You can buy gold, buy gear from AH, obliterate gear from AH, upgrade gear from AH with Obliterum. It changes exactly NOTHING. And in fact encourages this behavior.