Reading good food writers is the whole point of having good food writers. They can build an evocative sense of the time and place, the sense of why a recipie is the way it is. Its sometimes a personal journey, its sometimes escapism. And yes it changes - Elizabeth David sounds outrageously prissy to modern ears - but food has always been part of human culture, and as we evolve so will our food.
Its fine to read the wikipedia "plot" section if you want a shortcut. But its nice to know you can just read the whole book. Slowly.