I find this hilarious because I have seen both sides. Of course I have seen the side argued here many times; but when I worked my way through college, I worked at the Olive Garden as a waiter. You would not believe how many people believed our advertised food (brought out on a tray) was fake. Many of these same people would grab for them and then the surprise on their face was priceless when they learned they had to go to the washroom to clean the food off their hands. LOL...
Management hated it because it caused so much waste - they often had to remake the display after each such encounter, but we rarely prevented it - it was just too hilarious. Does go to show how ingrained it is in our head that it can't really look that good when served though.