It probably would also help with investigations too. If Joe Bloggs tried to sign up to attack bobsforum.com, got warned off by one of these services, and then a

It probably would also help with investigations too. If Joe Bloggs tried to sign up to attack bobsforum.com, got warned off by one of these services, and then a couple weeks later bobsforum.com had an actual attack, they’re probably going to knock on Joe Bloggs’ door first.