Our gritters have been out continuously. They come up our residential cul-de-sac several times a day (and night). I do question the need to have multiple orange flashing lights on the roof when gritting residential streets at 3:40 in the morning though. I appreciate the gritters being out, even if my car is permanently covered in grit all down one side, but it doesn't do much for a good night's sleep when your bedroom gets illuminated with bright orange flashes accompanied by the sound of a large lorry going past, and then again when it comes back down the road. Apart form the gritting wagon who else is about to see the flashing lights at that time of night?
As to delivery lorries, there was a live interview with a lorry driver, using his mobile phone, on BBC Newsnight Scotland on Monday night. He had left early that morning and got on to the motorway 10 minutes later. At 11pm he was still waiting to get to the first place he could turn round to go home again. I don't think he would get many deliveries completed that day.