I live on Long Island NY and honestly haven't seen empty shelves here. What I have noticed are some odd sales that don't follow the usual sales cycles - e.g. February is canned foood month. A large chain is running a sale on canned veggies for 77 cents a can. Odd when people generally buy fresh food in June.
Another odd one was Swift pre-seasonred ribs for $1.99/lb. With Swift closing two plants, the low price is unexpected.
Happily, I seem to have gotten through to my son (but not his wife). A blessing to have him living on the second floor of our home after my husband passed in January. He was actually talking about expanding our compost pile considering the upcoming food shortages. Sometimes they're listening when you least expect it.
We buy bulk dry goods, grains: rice, wheat, einkorn, barley, oats, rye, cous cous, quinoa. And legumes: lentils (green, red, French), beans (chickpeas, black, adzuki, mung).
They come in 25-50lb bags, and we buy from two different places that offer free shipping..
Once you get a basic concept of sourdough, you can make any baked good with it, even pasta - and pasta without eggs, if they're unavailable..
The initial purchase is "expensive" especially if you don't already have a grain grinder and other assorted kitchen tools for handling whole foods, but in the long run it's much cheaper, and more delicious.
Any food that's worth eating is also worth making from scratch with the absolute BEST ingredients you can find.