Okay, stereotyping/painting all with the same brush:
Do you find Brits to be more into brand names than Americans? And feel that if something costs more it must be a better product?
I've met quite a few like that, regarding clothing. Like, if a pair of jeans is more expensive, they must be better. Same with brand names and labels. In the US, the proliferation of shops like Marshalls, Nordstrom Rack, and constant sales mean you can get brand names for cheap, so paying more here just means you aren't a "smart shopper". Not sure if the same attitude is true away from cities.
As for food, my very particular MIL is very particular about the brands of food she buys, even if we're talking tins of soup. She's a frugal lady, yet she shops at M&S at least once a week. (Have to admit, the food is damn good out of there though.)