EDIT: Note that I said there some server-sided precautionary measures such as changing codes, validating purchases, etc.
It might be possible for a system to exist that disables such codes from use during purchase. Who knows... The implementation of that protection is unknown to us. However that does not erase the fact that gun-adding as we used to do it is patched/nonfunctional according to most of the people who tried.
I don't need gift any proof loool !
I know i can add a lot of item
I send you a picture in 1 hours MAX
I want to Develop this World,
But you Never Tell Me The Source Code ...