I know of one British fabric company: Makower UK.
http://www.makoweruk.com
If having a business located in the UK makes a difference in the prices, then maybe we can find a clue.
UK quilters, how does the price of Makower fabrics compare with the US brands? Over here, Andover Fabrics sells the Makower brand, and they are both priced the same. Timeless Treasures and Michael Miller fabrics are about the same price here too. What about over there?