They have all been painted in sombre colours as befits the time and place as not everything in the "Garden of England" is bright and cheerful. Most of the miners are wearing hard hats a few are carrying them on their belt at the back and just a couple are not carrying them at all. We have to assume the ones not carrying hard hats work above ground. Historically in Kent 4/5 did work below ground so a couple without hats is about right.
It looks to me as though these chaps are quite rightly upset about the actions of an American manager with a Scottish surname who has been brought in by the government to screw the miners while they, allegedly, sc[redacted on instructions of our lawyers due to ongoing police inquiry]ors.
Nice bunch of figures Clint and I think they deserve a couple of bonus points.