I've never seen anyone photograph food in a restaurant, but I've seen lots of photos of food that people take in restaurants. Scratch that, I saw some taking photos just last Saturday. I have seen plenty of group photos taken. It should be noted that the linked article is in a TOURIST locale. More people "out of touch", more people updating their statuses, and more people taking memories.
While I suspect that the article does exaggerate, it wouldn't surprise me at all that a touristy joint would see a 10-25% increase in customer turnaround time.