TBH I’m not a great price watcher, when I get back from shopping I couldn’t tell you to the nearest 50 cents or 50p what I paid for each item, but I do get the impression that things like butter, sugar, bog rolls, toiletries are cheaper in the UK. Even like for like - I seem to remember noticing that Lidl sell their identical fresh breakfast patisseries for less in the UK. But when I go back I stay with people so I can only imagine what the cost of living actually is. Perhaps imagining it is cheaper is just wishful thinking because I like to think that I’m not costing them a fortune to feed while I’m there .
Coffee beans can certainly be cheaper in France, I’m a coffoholic and I buy the 500g bags in Carrefour for under 5€ for everyday drinking - rough stuff but you can’t get coffee beans for that price in the UK. I take bags back for the people I stay with so that I don’t cost them a fortune in coffee. But good coffee beans in France are around the same price as in the UK. I also take back things certain things that mine hosts like that you can’t get, or can’t easily get in the UK - gésiers, confit de canard, cervelle, cheeses, rillettes.
I have to say that the lifestyle I share with mine hosts when I go back seems good to me, it’s different from my lifestyle in France but I wouldn’t call it better and I wouldn’t call it worse. They visit me, I visit them, we all enjoy both worlds. I don’t really see the point in trying to compare apples with pears. And I still don’t see what it has to do with the original topic of exchange rates and the issue of trying to juggle living in a country when your income is in a different currency.