Yes but there is a way around the problem -- you can list your number under the previous owner's name. Then whenever you get a phone call asking for <Previous Owner's Name> you know you can immediately hang up.

I agree it's not quite a perfect substitute, but it works fairly well.

Telcos have been charging for that forever. Most of your normal "landline replacement" VoIP providers do not. I suppose it was only a natural progression though for Comcast to charge for it, since that's kind of their MO.