1. Upscale western grocery stores and markets, ideally located within the biggest and most affluent city possible. Pikes place market would be a great example of what I'm talking about for you seattle folks.
2. Asian grocery stores, like "H-mart"
3. Farmers markets, but these are hit and miss, especially in smaller communities
Most other grocery stores, including Costco, Trader Joes, etc are full of extremely unhealthy trash slop. It's still extremely hard to find reliable low sugar options nearly anywhere, including at health and "organic" oriented grocery stores.
America just sucks for foodies who don't have unlimited time to get through the slop.