After playing borderlands 2 for the first time this weekrnd I became annoyed with destiny after 5 minutes of playing weekend coz I can there trade everything and anything with anyone and the reason why we cant trade in destiny is simple its the same reason they have ascendant materials in engrams and nightfalls it decreases the chances of getting the best the gear making you as a player want the desired item even more so you go and invest even more time into the game. In my opinion bungie won't allow trading just so that we gamers spend more time in the game grinding rng.