It came up for this specific view:
Now, I can't reproduce it, but he sent me a picture showing the ad overlay directly in the picture:
As you can see, there is this little icon that is overlaid on the picture. When you click on it, it is one of those AdWords local extension. Is this a browser bug or a feature? I am not sure.
He did share a screen that shows he has this ad extension live in his AdWords account:
I've never seen this on in-store business photos, have you?
Forum discussion at Google+.
Update: This seems to be a bug according to Google.