if you think that some stupid spam mailing with rebills is black hat.. hahaaha
There are worse crimes that can be committed with a computer no doubt but it's not just non-compliant rebill spam. What the OP describes involves phishing into email accounts which is unauthorized access to the network of the ISP. Each count of computer fraud like that is maximums of 5 years in prison and a $250k fine. If they find the money trail and you get wire fraud tacked on that's about 20 years max for each count.
I don't think it's blackhat, I think it's dumb hat.