There's a balance between buying cheap, healthy, and convenient, and it's not always easy to feel like one is successful at all three.
Particularly with prices going up quickly, it's helpful to have a sanity check that it's not lifestyle creep on our part, so we look at the USDA cost of food reports, updated monthly, and I presume are still accurately done.
https://www.fna.usda.gov/research/cnpp/usda-food-plans/cost-food-monthly-reports
Not a fix or tip for eating cheap, but makes it easier to know when it's not you, it's the system.