This issue is brought up many times before....and rejected every time.
It is really cheap to buy credits........or you could ask someone to give you a credit code in exchange for some cards.....i dont know if clint city aproves this though....
We do understand there are fair and honests players that cannot purchase credits easily and they miss the selling feature.
Unfortunatly, there is also a small amount of unfairs players that would be able to completly destroy the future of the game by abusing the system if
we do not have this rule in place.