An analysis of the buying profile of FCM's 450,000 card holders using the Overdrive and Dialcard networks has seen the supermarket share rise from 6% in January to 9% in August as drivers chase incentives such as free groceries, and in the year to August 1996 the supermarket share of the PHH total moved up from 7% to 10%.

At PHH, Keith Greenhead, divisional manager - fuels, said: 'The company car driver doesn't give a damn about the cost of fuel because someone else is paying - unless their company has a proper fuel management policy. What you are seeing is just more evidence of that fact. If companies don't have a policy drivers will pursue their own interests and it is the companies' own fault.'

FCM's managing director Jeremy Snowden agreed that the supermarkets were winning business by using 'modern and sophisticated incentive schemes'. He warned: 'The fleet manager's responsibility is to ensure sensible fuel buying but incentive schemes can work directly against that aim. What fleet managers need are the tools to allow them to work with their drivers whilst achieving the lowest possible fuel prices.'