[Dudebro]

Well people can and are routinely banned from sites, IP blocked and reported to the police for harassment in cases like this. Your ISP makes you sign agreements that you have to abide by online, you breach that they can just shut you off completely. If what you do is illegal and reported by the website the ISP is usually legally obligated to pass it onto the police. So they may not be arrested for trolling but the police paying a visit to your house to question you after your internet is shut off is a pretty strong message.