I do my purchase from grocery store is a retail store that primarily sells food.
I do as well!  What grocery store do you shop at?
Wal-Mart Stores, Inc., doing business as Walmart, is an American multinational retail corporation that operates a chain of hypermarkets
Are they the largest grocery store in America?
Walmart has 11,703 stores and clubs in 28countries, operating under 59 name categories
Wow!  That sure is a lot!  I did not realize they were that big!  Are there any other brands that are any where near the size of Wal-Mart?
We also have the Asda stores ,Grocery stores often offer non-perishable food that is packaged in bottles, boxes, and cans; some also have bakeries, butchers,
Yeah, they really are convenient one-stop shops!  
Some large supermarkets also include a pharmacy, and customer service, redemption, and its an all in one shopp