https://9to5google.com/samsung-smart-fridge-ads-how-to-turn-...
Update 11/14: Samsung has commented on the image posted to Reddit, noting that the ad format shown on the smart fridge display is not one that would appear over the cover screen. Any ad shown would be limited to the cover screen widget, which displays news, weather, and calendar events. Those slides rotate every 10 seconds or so, and an ad is looped in around every 40 seconds.
It appears that the ad shown in the Reddit photo is of the fridge’s Samsung Internet app. Through that, an ad seems to have shown up organically through a third-party website.
Samsung notes that full-screen ads do not appear as part of these recent software updates, and users shouldn’t expect to see ads that take up the entire display.
‘Shown up organically’ seems like a very generous interpretation to me - it seems far more likely that someone viewed it deliberately for the purposes of staging the photo.
On the other hand, I don't trust a company that puts ads on their fridges.