In Australia when pay/cable TV first came in it was ad free, but then ads were slowly added to it, first just ads for content on the channel, but then normal ads came in. People were rightly angry about this because they thought that by paying for TV they could skip the ads.

However it turned out that by paying for TV they were signaling to advertisers that they were better off (and willing to spend money for things) than regular free-to-air TV watching people, and therefore their eyeballs were worth more. So now pay/cable TV in Australia has more ads per hour than free to air TV.