This is in the US. If you search online, it seems to be a commonly reported issue, with some articles saying LG started ramping up the ads a year or two ago. Maybe older firmwares don't get the ads?
I'm literally on the very latest firmware on my LG CX, connected to the internet, use the apps all the time and I have zero ads on mine, never did anything to block them either - I'm in the UK.
I wonder if that's actually some kind of EU/UK regulation that's absent in the US that's preventing this.
Mine started about a year after I bought the TV with no updates done (and the TV rooted, blocking updates) in AU.