4Chan is just a community. Sure it is full of immature people who participate in illicit and often illegal activity, but the last time I checked, Verizon is not the enforcers of Federal, State or Local law in any jurisdiction. If Verizon thinks that members of 4Chan are participating in illegal activities on American soil, then they are well within their rights (as far as I know) to present their information to the proper authorities who can then take action.
Of course this will raise the usual "Your Rights Online" discussions about whether it is legal or a breech of privacy for Verizon to release that information.
Nonetheless, you can't have Net Neutrality and then kick 4Chan off the internet. It just doesn't work that way (except in China).