Google is using a gray shaded background color for some of the results within the Google Shopping Ads carousel. I was able to replicate this, where for some images, Google thinks a light gray background works better than a white background. This is not tiled, where every other result is shaded, it is based on some other algorithm, maybe the color of the photo of the product?
Here is a screenshot of this:
Saad AK shared videos of this on Twitter:
— Saad AK (@SaadAlikhan1994) June 27, 2022
I am not sure if this is new or not but maybe it is?
Forum discussion at Twitter.