BIWI - "But why, Cote?"
I expect recipes to start from basic ingredients because I might want to cook them myself when I have the time, and I would want to know what to do then. Specifically re chickpeas, how long to soak and how long to cook them. When I don't have the time, I can substitute tinned chickpeas, no problem.
And I like to cook them myself because (1) I think they have better texture & taste, and (2) they are more nutritious.
You cook entirely with tinned ingredients, if you like. I am only telling you that personally I prefer to use fresh produce when I have the time, which is why I expect recipe books to start with basic fresh ingredients.
Btw, I just checked my Ottolenghi book and it does for example start with dry lentils and says "Wash the lentils in plenty of cold water. Place in a large saucepan with the water, bring to a boil, and simmer for 35 minutes until soft. Skim off any scum that rises to the surface during cooking". I think it's a good thing that he doesn't just say "Open a can of lentils". Fine if you disagree, though. It is not like we will ever end up in the same kitchen and argue about how to cook the lentils 
I also checked the one English cooking book I have, and Jamie Oliver indeed uses tinned tomatoes for ragù, but fresh tomatoes for some other dishes. He also starts with dry lentils ("Simmer for 20-25 minutes (topping up with water if necessary) until the lentils are tender but holding their shape") and ears of sweet corn ("stand each corn up tall and carefully run a knife down the cob to cut off the kernels. Drop the corn kernels into the pan, add the thyme and stock, and simmer for 20 minutes"). Sure, I would use tinned corn most of the time, but personally like to have the recipe tell me what to do if I have corn cobs one day.