But you can take a picture of the book and post it online, right? Because you're not scanning the contents of the book, the reason it has value. So why couldn't you post a picture of your food online, no one can eat it online, the reason it has value
Precisely! The intrinsic value of the food is (or should be) in the taste and to some degree aroma, not in the appearance!
I know presentation is much hyped in the food world these days, but honestly, I would never select a place to eat based on how good its food looked. Most of my favourite places to eat are sharing-dish places (think Thai or Viet-Namese restaurants), where everyone orders a dish that sounds good, and everyone takes a bit of everything on the table. While the food definitely looks good (and smells great!), I'm pretty sure it's just ladled into the bowls and brought to the table with 'maybe' a lemon wedge or two tossed on top.
That being said, I suppose I might avoid going to a place that served three green beans draped over a poached strawberry as a main course, but I wouldn't have to see a photo of the plate to know that I would never eat there, a brief description would do.