With the volume of mail declining worldwide, the Royal Mail (the UK version of the USPS) is trailing new ways to make money. One is having carriers set aside their delivery duties and instead capture GPS data of front doors of homes and businesses.
The trial is in Essex, Cambridgeshire, Lincolnshire, Norfolk and Suffolk, and the Royal Mail is making it clear no personal information or photos are being collected.
The "Pinpoint" project webpage offers a Q & A but doesn't really explain what will be done with the data. My sense is it will be sold.