Because there is documented illegal activity going on? If hotel staff were alerted to a murder within their hotel, they would respond by calling the police, not sitting on their hands because the murderer paid for the room.
Calling the police on discovery of a death is their duty, ejecting the alledged murderer is not. What you're talking about here may be akin to giving Cloudflare the power and the obligation to act as police force, judge, jury an executioner.
Besides, if a domain owner can switch to Fastly, Akami, Cloudfront or any other CDN, are we really solving this problem in the right place, or are we just giving Cloudflare extra responsibilities and powers that they shouldn't have?
Cloudflare isn't even telling the police any of this information. They took it from OP, said "OK, we will continue to profit off this client," and swept it under the rug. They don't have to be the judge jury and executioner here, they should however pass that information along to said legal system rather than continue to turn a profit off of the criminal behavior.
