My cat drinks milk. Other animals probably would drink milk if they had access to it. The opposable thumb thing is really handy for accessing milk, and the whole thing about being able to raise livestock - I can't think of any other species that do that, so that right there rules out, say, armadillos having milk cow farms.
Bottom line nutritionally, IMO, is that if you enjoy milk and have no digestive issues, raw milk is the way to go, but you certainly can find complete nutrition without it. Sometimes if I'm at the farmers' market or one of my local farms and I see some for sale, I'll buy it and drink it down, but I go long periods without it.
A way a lone a last a loved a long the ... riverrun, past Eve and Adam's ...