There were some discussions in the same spirit on previous smart TV threads on HN but I'm not fully sure if there was any real example, or was it just hypothetical discussion which became an urban legend. Any particular examples other than "people say"?
I don't see why they can't make a deal with Comcast to have access to their public Wi-Fi network so that their Smart TV's "just work".
Wait until TVs contain their own cellular modem that can connect without your approval
Did that happen for real?
If you check the other comments in this thread, there aren't well documented reports, just hearsay. Given that this is so trivial to replicate (all you need is a smart tv and router/smartphone tethering), you'd think that if the claim were true there would be well documented cases of it happening.