I like the variety and quality better in the UK, but I think that's down to living in the country here. I was always in a city in the US - on the plus side, that meant big shops with lots of variety of packaged goods; however, there wasn't as much in the way of fresh produce, cheeses, etc. beyond the basics. We did have Whole Foods which was fine but overpriced, and there were a couple of farm stands which would be open in the summer - but those weren't anywhere near where I lived. Here, I have access to farm shops, farmers' markets, etc. all the time, year-round with fabulous in-season fruit/veg, fresh locally caught fish, and cheeses from all over the world (not just Cheddar!).
I think a lot of this has to do with where you lived in the US and where you now live in the UK. And the rest of it has to do with personal preference. It's not really an argument anyone's going to win.
(As for the fruit juice debate, I've never in my life had any problem finding real juice ANYWHERE, so I'm a little baffled about DavidO's inability to source it!)