[Ignitionnet]

http://www.oft.gov.uk/shared_oft/bus...t-of-Scope.pdf

Complex pricing This covers a range of practices, but includes those
pricing practices used by retailers which might make it difficult for the
consumer to assess the unit price, for example 3for2 offers and 'free'
add-ons, or where complex price structures might make it difficult for
consumers to compare prices.