There's all sorts of things we live with by ignoring them; just pass by on the other side of the street. One is milk.
I'm reminded of that by this extension post on milk quality.
Note the emphasis on "clean" in the writeup. The dirty little secret is that some amount of manure gets in the milk. It's inevitable. It's something we don't like to dwell on, something I didn't dwell on even when I was growing up on a dairy farm drinking raw milk and fully aware of the fact; just something we live with by ignoring.