> Making a telephone call rests on the same convention: you are allowed to make someone spend time on the phone with you, because you're spending your own time.

I personally, absolutely do not think of it that way. Whenever I get called by a call center, I always immediately say "not interested" and drop the call. It's rude, but I think these companies are not entitled to my time.

Because of that I think the problem is already there. This is certainly another step in the wrong direction, but thousands of workers in thousands of callcenters are basically already a human botnet.