I buy stuff from all sorts of places. I’m pretty serious about food and cooking, and I run through a pretty wide variety of cultures and regional variation in making my food. So for me, this is how I buy:

Fresh produce in season: street markets

Fresh produce out of season (greenhouse grown or shipped in from another latitude): Whole Foods

Mainstream American prepackaged foods: nearest big box corporate supermarket.

Day to day meat, dairy, and seafood (chicken, beef, pork, shrimp): Whole Foods

Specialty meat (aged stuff, unusual cuts): local specialty butcher, ethnic grocery stores

Specialty seafood (live seafood, less common items): specialty seafood shop

Fancy cheeses: cheese store in my neighborhood, occasionally Whole Foods

Various ethnic specialities (Kim chi, tortillas, paneer, certain types of Chinese/Korean/Vietnamese vegetables, Mexican/Indian spices) that are perishable: ethnic grocery stores

Unusual or imported prepackaged or shelf stable foods/spices: ethnic grocery stores, Amazon, other online stores depending on the item.