iTunes card payment method??

Very many people have received iTunes cards (through it being a gift), but won't even need them. Including my friends, online friends, and myself. Even though there are several great payment options, there should be one including this because of how often we receive these and practically have no use for them maybe because of us already having money in our iTunes account and would like to spend it elsewhere. Adding this could result in great feedback and more money coming towards you, Riot.