Re butchers and how expensive meat is - in our area (inner SE London) we have two independent butchers within walking distance who both market themselves as selling premium meat. They stock unusual cuts, give information about the animals' diet and welfare, information about their suppliers, etc etc. Local equivalent of Borough Market, I suppose. I never buy there because we don't eat that much meat and it's more expensive than I'm prepared to pay.
We also have butchers and a fishmonger operating on the nearest high street who sell in high volumes and their selling point is price, purely and simply. I never buy there because I'd have concerns about where the meat has come from, to be honest.
When it comes to fruit and veg, I would buy from the market on the high street if it was nearer, but I wouldn't expect the produce to last as long as it does from the supermarket because I don't think it's been kept under the same conditions prior to sale (i.e. it's spent longer out of the fridge and it's not packaged to extend its life). The market stalls also sell entirely on price.
We also have a market nearby which operates for a few hours on a Saturday. I haven't been there for years but I think it's still a mixture of street food (i.e. expensive/exotic coffee and fast food) and farmers' market type stalls selling fruit, veg, bakery, olives, fruit juice and probably meat. Very expensive last time I was there. Totally out of reach of most people in our wider area.