You can shoot the stalker, you most likely won't be able to shoot the police without someone noticing.

A situation like that would likely precipitate other companies seeing the opportunities for customers (the comcast subscribers) and making their own services, something as ubiquitous as youtube practicing this kind of policy would suddenly find its ubiquity usurped by someone not restricting themselves to isp's willing to pay.

There's no law that says they have to take your money, or that they have to provide you services. Its only restraint of trade if, as part of their agreement, equivalent services are blocked by the ISP.

Why is this in YRO? this is a GOOD thing. Granted, Microsoft could do well to make it harder for these entities to survive by virtue of changes to their OS, but there's only so much you can do to curb the naivety of the average user. Not that there's a whole lot that will come out of something like this, I suspect that most of these ads come from a jurisdiction that cares little for American Jurisprudence.

The cops are just as likely to beat the crap out of you and throw you into jail as they are the suspect, more so as you're there and the suspect isn't, especially if you get short with them, they like to call that disorderly conduct.