Often, despite the ~10% user/activity loss, profit is increased by increasing ad load. And this is in tech contexts like web browser/smartphone/music-streaming where switches and upgrades are pretty easy and often done anyway. The loss from equivalent ad burdens on TVs is probably much less. (People replace their smartphones more often than their TVs!) The ad revenue also lets them discount the upfront price of TVs (I think I saw an article on HN that the discount due to advertising is at least $50/set?). And then there's the time-value of money: $1 up front in exchange for $1.10 of lost sales 10 years from now when they (maybe) buy an alternative brand is a pretty sweet deal for the seller.
Some consumers may hate ads like poison. But most of them are just fine with it, and prefer the micropayments to the macropayments, as it were.
