The additional labor cost paid for something to be made simpler to consume – “opened” in this case.

Despite considerable effort, still found it hard to actually “open” this little bugger – the subjective definitions of “ready to eat” (i.e. norms around bones and their removal).

Consider the ease unopened walnuts are found in your local context compared with the value/labor added forms (opened, chopped, etc.), and what that says about expectations around food and cost consciousness of consumers in your local context.