I stand by that what I've mentioned looks fake (especially the strawberries and the sauce) but I think that would be a great exercise. Your brain believes what it expects. I had the expectation that these were renderings so it was easy to pick out flaws.
Be interesting if people could correctly tell which images are renders and which are real, with > 50% accuracy, if they were given 50 sample images.
Because being told that an image is computer generated, and then saying "Yep, it's unrealistic" isn't particularly compelling argument.