We simply don't have the infrastructure necessary to deal with the problem as well. There isn't enough gritters etc. available to clear and salt the roads. Okay, this stuff is expensive, but when you add up the cost of the economic damage done by this and other incidences when "poor" weather has paralysed the UK, investing in equipment and personnel to deal with it is necessary. Moreover, London is one of the world's key financial cities, so it's not just business etc. in the UK that suffer.

Ayrton Senna: WDC 1988,
1989, 1990, 1991
McLaren: WCC 1974, 1984, 1985, 1988, 1989, 1990, 1991, 1998,
1999, 2007McLaren: WDC 1974, 1976, 1984, 1985, 1986, 1988, 1989, 1990, 1991, 1998, 1999, 2008