I imagine this was used to keep food and such cool, not milk cans- would be too much trouble to carry cans up to the house and into the basement, and then out again. Usually the ones for the milk cans were in the milkhouse- put the cans in after milking, leave them until a few minutes before the hauler comes, then carry them out to the stand. Or extend the road out to the milkhouse, and the hauler goes in and gets them directly out of the trough. We shipped in cans for the first couple years my dad milked- shipped to Darigold, I was 3 and called the hauler the "daddy-goat man". Folks got a kick out of it, because the sour old guy kind of had the personality of a "daddy goat".
Friends bought a property with an old milkhouse with spring trough in it- roof was shot, but they were going to rebuild it- but this past winter, the whole thing collapsed, and they just covered it over. Would have been nice if they had been able to save it, but, things happen.