It's like many things in life - cheaper to do it yourself, but many folks don't want to take on the admin, get the driver to sign the authorisation, chase for the return of the signed forms, spend the time making the calls, figure out what the codes mean. We take on the task and the customer pays the money in return for the service.

No-one has to pay the £10 and many don't bother, but some firms see it as money well spent as they can demonstrate that they took proper steps to avoid a potential problem - and if that keeps one of the directors out of prison on a Corporate Manslaughter charge, it is very good value.