Is it all these people in referral list are abusers? Even if they are abusers,
They are not even people. They are email addresses, fingerprints and VPN IP addresses used by a bot. The information is in no way personal and might be useful to other services doing free giveaways to help them prevent theft and fraud by the same person.
I deliberately did not disclose the individual's real email or IP used on their master referrer account.
Well, that makes sense. Because initially for me it looked these emails might be of real people. Often abusers are using very similar emails, like
user1@gmail.com,
user2@gmail.com and so on.
And as said above, sometimes posting personal data is needed to identify scammers and prevent them to continue their activity.