Likewise cable TV. You pay for a subscription and you also see a lot of ads (more than on OTA TV, which is one of many reasons I cut the cord.) In the early days of cable networks, many had no ads because it was thought they could survive on subscription revenue. That idea didn't last long.
As a whole, broadcast and cable TV is (used to be) a captive market. It was very possible for channels to synchronize or nearly synchronize their commercial breaks which meant that they could get away with charging for content AND showing ads.
The proof is that the minute add-ons like DVRs and set top boxes like Roku came along, the first thing people did was to bail on the old TV model.
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