I follow whole30/paleo and have kept consistent for 18 months.
I eat no grains of any kind, no sugar, no artificial sweeteners, no legumes (with the exception of occasional snap peas), no alcohol, no dairy, no corn, no MSG, and no soy/soy-based products.
There isn't a whole foods near by and even in shopping there I find very little that I can actually use (and the mark up on the other items I can get anywhere else is significant). Trader Joes also has very little.
I buy my grass fed beef from a local butcher and will often buy locker packs.
Otherwise I do almost 100% of my shopping at Costco and pick up a few specific items at local grocery stores (small quantity type items).
Our food bill has actually stabilized, but not gone up. We don't eat out nearly as much as we used to, we don't waste money on snacks, but cook more at home and pack our food on outings.
I've had amazing results on my health. Those that I know who have gone this route have also had
amazon results. Once you get used to it and break the cycle of a processed diet it really is simple, filling (no portion measuring or calorie counting!), and satisfying. I simply don't crave anything anymore because the food I eat really satisfies.