Have you gone shopping in the states, in a biggish city? Trust me, the choice here is not only different, it's limited. Now, don't get me wrong, we're not talking Russian breadlines limited, but in comparison to the variety of stuff easily available in the states, it's limited. IMO
& It's not a matter of merely going to say, a Target vs having to shop around here. Even the variety of small shops, and different types of bigger shops, and everything inbetween is staggering.
I think it's a combination of the free market, capitialism on steroids, the support for small businesses and innovation, and the truly multicultural population that creates big enough demands for all sorts of things, all of which the UK is lacking or has in very small doses in comparison.