Yeah I'm honestly not sure why people would be surprised at this comparison - Whole Foods and Trader Joe's are specialty stores. Nobody goes into them just to buy a head of lettuce.
Trader Joe's has their own in-store brands for tons of products, which has spawned various guides on what should/shouldn't be bough there (https://www.thepennyhoarder.com/save-money/what-to-buy-at-tr... for example). CVS, on the other hand, is a far more general store. They both sell food, but they're not in the same market segment - so the comparison is strange.
Trader Joe's has their own in-store brands for tons of products, which has spawned various guides on what should/shouldn't be bough there (https://www.thepennyhoarder.com/save-money/what-to-buy-at-tr... for example). CVS, on the other hand, is a far more general store. They both sell food, but they're not in the same market segment - so the comparison is strange.