You mean processor/bank/merchant account, not merchant. In the parlance of the payment industry justfab is the merchant in this story.
And yes, there are scammers that have processors / banks lined up but they burn through them at a rate of about 1 every 8 weeks or so, and each time that happens they forfeit a large amount of cash. There are not that many merchants willing to play the game that way.
50 chargebacks or 0.5%, whatever gets hit first and you're in trouble. Reputation damage to the CC companies and you're out for good. Merchant account hopping is not a long term viable strategy.