just the usual, sainsbury's, ocado, tesco, co-opt. we have tried local butchers but usually they are not open by the time we get home.
to be fair, i do think the farm to table practices here are probably healthier, more humane etc than the US, which is great. not as much chemicals. but this also means that sometimes veg you buy might have mold on it when you buy it and not as robust.
also a little tidbit and an example of what i'm talking about. the flour here is a bit different than the US. Flour from the US is actually banned because it's heat treated and bleached, which some studies link to cancer. BUT, if you have tried baking here, cakes, etc don't come out as moist and the texture a bit more rough. so while the flour here to better for you, baking fancy cakes here might be a waste of time and money because they won't come out as well without the same ingredients. if anyone else has had a different experience, let me know!
i'm not saying the UK should adopt the US's questionable food practices, just pointing this out.