We are lucky to come under the haven't really a clue heading. So much depends on what we're doing. DH shops in town daily. The local fruit and veg shop has a small holding and produces a lot of the veg, there are three butchers, two of which win prizes, serving locally produced beef, free range pork and chicken, etc., and one specialising in game. There are two good independent bakers and a little lady who makes cakes. Plus there are twice weekly markets and a monthly farmers market. The franchised supermarket is excellent and specialises in local produce and small producers. We are truly spoilt.
About twice a year we go to Sainsburys to stock up on beer and things like Rachel's rhubarb yoghurt which DH likes. We like to cook and because we shop for what we need we rarely throw any food out. Also, comparing with friends outside town, our portions are much smaller. Good quality means you need less. One free range chicken breast does two good portions while a fast grown intensive bird serves one as the meat is less dense. Supermarket carrots seem watery.
I don't think we spend more proportionately than we did before we move here and did a weekly Sainsbury shop. Certainly the young families who have to watch the pennies use the butchers, bakers and green grocers so they must be competitive with the local Tesco where they do the rest of their shopping. Tesco gains from the people in a hurry and the can't-be-bothereds.