I ordered a burger. Or I thought I did.
What I got was a fish-cake in a bun.
And that's exactly why picture menus fail. A bowl of soup? How do you photograph that? If it is green does that mean pea soup? Does it mean asparagus soup? Does it mean lentil soup? They will look identical.
Similarly a chicken-burger, vegetarian-burger, fish-cake in a bun, or hamburger will look identical. You need the text to differentiate them. (Not to mention the text is more concise. Just imagine "jacket potato with toppings such as: tuna, cheese, beans, salad, tomato." How many pictures do you include before you just give up and say "More available"?)
Restaurants don't have much money. Single colour printing; dual colour printing; are cheaper than full colour printing. That cost recurrs every time you change your menu. You don't want anything forcing you to stay to the same menu.
Photographs of food are associated with low quality places.
I do agree that a photo of the food would normally be a good thing. It's more accessible than writing - to people with a reading disability; people with a learning disability; people who don't speak the language the menu is written in.
Plus you would still need to have physical menus as backup for those customers that don't have smartphones, are out of battery, etc.
I've seen some sushi spots have their menu on an iPad; and it worked pretty well. However, personally I also enjoy the conversational aspect of placing an order with a human server (with the interaction influencing the value of my tip).
This virtual menu concept brought this article to my mind: http://www.slate.com/articles/business/moneybox/2014/07/vira...
Text allows us to talk about the future. Photographs only let us talk about the past. I can write a description of a dish I plan to make. I have to make the dish to photograph it. A week later I can edit "a medley of peas and carrots" to "a medley of peas, carrots and chicken gizzards" without setting up lights and trying to photograph chicken gizzards in a way that distinguishes them from chicken livers.
The standard way to visually express a restaurant menu is by showing the actual food...e.g "Here is today's special" or "here is the desert cart."
When I couldn't clearly do so, the boyfriend pulled out a large picture book and started flipping through the pages. He came to one with an image of meat/chicken and a large, red circle with a slash through it. He pointed at his girlfriend, then at the picture, and the waiter nodded. She got the vegetarian version of a bean dish that often has some meat served in it as well.
I was impressed. The book was indexed and divided into categories for everything – bathrooms, the airport, food, hospital visits, etc. It covered so many cases that I had needed addressed in my travels and many more I had never considered needing to communicate. I travel enough that I have sought this book for a decade, and I would pay good money for an indexed app that could do the same thing.
Menus are just the tip of the iceberg.
If you use photos, you need a professional photographer with a studio. You can't just snap pictures in the kitchen because the food won't look appetizing. In the end, it's all about effort vs gain. And a text menu takes the least effort and provides the most gain.
Also I never see a menu full of pictures good looking. Typography > images.