To me, it's more of an anti-gotcha thing. So the DM doesn't get to say "It's a bright sunny day out on the ice, so you need to roll a Con save to resist snow blindness." That's the kind of thing our ranger would know about and pack blinders for (though those might have other effects like disadvantage on Perception checks). It won't help us if, say, someone falls through the snow into a crevasse. At that point, it's equipment list time.
It's basically the same principle as things like "fishing tackle" in the PHB, which includes "a wooden rod, silken line, corkwood bobbers, steel hooks, lead sinkers, velvet lures, and narrow netting." Realistically, those are all things you'd buy separately (and, in a pre-industrial world, likely from a number of different craftspeople). But you don't have to sweat that, and the DM doesn't get to tell you you forgot to buy a whatsit so you don't get to try and fish.