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
Wow, they are incredibly cheap in the US - in Australia they are nearly double the price per kg.
Oh yeah he mentions his source is Walmart in a specific state, but amazon is more consistent here.
Always interesting to hear how different stuff is in different countries!