This has to be something that's only legal in the US because I've never had ads on any TV that I've owned. Never even thought about it, I just get a random big TV and it doesn't have ads.
Admittedly I haven't actually bought a TV in about 10 years so it is possible that the ones I'm getting from family members and friends are just very well researched, but I doubt it knowing them. They will have just got whatever is biggest.