Bleach Brave souls orb method

I know server side games cannot be hacked, but there are multiple guys on various sites and even facebook that sells orbs (the game's currency) at an extremely discounted price, there are proofs of it so its not a scam and i don't know how they do it..
I don't think they card the game cause that'll most likely end up with your account banned.
Do you know this method or have some clues about it?

I'd like to know as well..
I was actually thinking they are just buying it legally but then they turn to Apple or google and ask for a refund..
Worked for me when I tried it with my alt..

There is also a possibility its stolen credit cards.
This way the person who sell you orbs cheap, use a stolen card, pays for everything and you get the orbs and he gets money.
When the owner complain about his card being used, slab still get their money, so no orb detraction.
The one who pays for the loss are the insurance companies and the banks..

There is the last possibility of a tweak that allow you to buy in-app purchases without actually paying for them..
I know its open in some games/apps..

But I really think the most probable is the stolen credit cards..