That last photo has convinced me that the original is a photo of the employees and owner of a fairly large dairy farm.
Metal buckets, white clothing and hats.
If you had ever milked a cow you would know why they are wearing hats.

There are two halves to a dairy farm, the grass, the hay, fences calving etc, and the milking side,
Milkers dress in white and handle the milk from when it leaves the cow until it leaves the farm,
Farm workers muck out wash down and grow the grass, and move the hay into the cowshed.
A modern milking parlour feeds the milk into a bulk tank straight from the cow, with no human contact, but you still need to be sterile to dip your jug into the bulk tank to pour on your cereal.
Just my thoughts, but a close relative still milks 150 cows, as did his father and ggfather
Mike