The public certainly has a right to know where retailers procure their goods, but they also have a right to reasonable prices, service-orientated staff and a pleasant shopping environment. Wal-Mart provides all of these in spades, which is why it is so popular. Despite great improvements in recent years, British retailers still have a very long way to go. Perhaps Mr Gummer prefers ill-informed staff, badly designed stores and high prices - but maybe he just never does his own shopping.
He claims that Wal-Mart will destroy the British high street, as he implies it has done in the US. In fact, US high streets (downtowns) were destroyed long before Wal-Mart became successful, by the rise of edge-of-town shopping malls, which continue to thrive.