They don't host attacks. They don't even offer a hosting service for that code to run on really. Those attacks come from botnets, mostly hacked IOT devices and servers across the web.
That’s a nice website you’ve got there. It would be a shame if someone DDoS’d it. Hey btw, I sell DDoS protection services. Gee, isn’t that just so convenient!
Not a racket when you see how common it was before Cloudflare.
I may be wrong here, but isn't this what Cloudflare Workers are?
It would be pretty bad at DDOS attacking.