Wel, they could, but ISP's (as well as regulators btw) are fairly reluctant to block 'popular' services. Companies generally use the legal system to fight back.

Wel, they could, but ISP's (as well as regulators btw) are fairly reluctant to block 'popular' services. Companies generally use the legal system to fight back. They don't go around just ignoring laws when caught or scoff at verdicts. Facebook has already said they will comply but appeal.