*** Tesco Swingers Club ***

Re Wal-Mart
I don't think you're comparing apples with apples.
If you compare Asda with Tesco it would be a more sensible comparison, but even then Asda is North-heavy.
Wal-Mart, operating inside the US, will have significantly reduced land and construction costs psf.
Additionally, the minimum wage in the US afaik is much lower than it is here.

Bottom line is that the UK is an expensive place to run a business, which is why (apparently) we earn so much. Or perhaps it is t'other way round.

International like-for-like comparisons would be interesting though, if anyone has that data to hand.