Regional Variations In Store Stock

Yesterday at Giant, I tried to find Maypo. Usually this is by the oatmeal, but I found, much to my surprise, that they didn't have it. Today I tried Safeway, which also didn't have it.
Safeway, on the other hand, stocks Tilamook Cheese, which is from Oregon.
It's a bit frustrating, since brands that I've taken for granted in New York are difficult to find here. At least they still sell Campbell's Soup.