This was an interesting article from the Citizen, some good explanations there from LCC including gritting certain areas, which don't have the traffic or footfall, and would become ineffective.
Lancsdave ... see Question 6 ..
Lancashire County Council chief answers your gritting questions (From Lancaster And Morecambe Citizen)
If you can come up with decent costings and time and motion studies to grit all the pavements, Ken, I will nominate you to become an Alderman of the Borough..
Haven't got my freebie yet, but Hey Oh .. will do for the next freeze over.