Actually, in my case, the co-op is smack dab in the middle of town, right across the street from the big chain supermarket - you can walk from one to the other. It also has a much greater variety of items available than the supermarket.
For example, the bulk section carries pastas made from not only your standard semolina, but also whole wheat (more than the SM), rice, quinoa, buckwheat, spinach, and artichoke to name a few. Not to mention all the varieties of whole grains, flours, beans, lentils, nuts, etc. Since they're sold in bulk, they're cheaper.
Shopping there is MUCH more convenient than the supermarket. Maybe I'm just lucky that this type of thing is important enough in the community that there's a market driven demand for it. I'm very happy to have that choice.