https://consumerist.com/2017/08/03/people-are-shocked-that-tv-signals-over-the-air-are-free-and-legal/

Were you aware that you can get some local major network channels for free, without having to pay for a cable or streaming service subscription? If you were, you’re ahead of 30% of adults, most of them young enough that they wouldn’t remember the fuzzy, rabbit-eared past.

According to The Wall Street Journal that statistic comes from a survey commissioned by the National Association of Broadcasters, a trade group for broadcast stations, who are the ones paying for the transmitters that put out the signals that now only a minority of Americans use.