The primary targets in this data breach were moderator credentials, according to 4chan spokesperson, who said that they kept detailed logs of what is accessed in their database. Those users which the attacker wanted to expose were informed about the breach and offered lifetime passes or refund of the premium account.
Also, there was no financial implications of this heist since 4chan does not process user's payment information directly. It is done securely by Stripe. This vulnerability was quickly patched and users were intimated that all measures will be taken to mitigate such attacks in future.