i don't think it could because Bungie\Activision have designed destiny to keep you coming back by little victories like finally getting Gjhallahorn or a legendary engram but trading would mean that you could get your favorite Guns or Armour without trying bringing the overall play time down. Think of Destiny as a Massive Casino and ever kill or activities is a spin on a slot machine if you could give someone a wining score strait up would give you high hopes and with the bad RnG you would Burn Out quicker and stop playing so you wouldn't buy the DLC's and not making Bungie\Activision money.So to stop this Destiny has been designed to give you victories though small enough to keep you playing it.Destiny also flatters you to keep you playing like" Guardian i can't believe you killed that guy im very impressed you are the best"