So that you pay for both.

Not even the mafia has it that good. You only pay them so they won’t beat you up. Imagine if you paid them to beat you up and then paid them to protect you from them.

That's how you profit

Learning from Cloudflare: Host malware and DDOSsers AND provide protection against them = $$$

I feel my question is naive in retrospect.

E.g. to secure the quality of training data?