Stolen from Reddit
https://www.reddit.com/r/dataisbeautiful/comments/1ftmkwt/oc_foods_cost_vs_caloric_density/
But I loved it. Also this has Shrimp removed, because it was on the OG chart due to an error and this is an updated version.
EDIT: Here is one for protein! https://www.reddit.com/r/budgetfood/comments/1fp2ytb/foods_cost_per_gram_of_protein_vs_protein_density/#lightbox
People who live in poverty could use this graph to plan the cheapest way to get their calories to avoid starving with very little money.
Is that what you're missing?