The jury's still out with me, but I have to admit that I think it's important to recognize that humans are the only species that continue to drink milk after they are weaned and from an animal that isn't even their own species, no less.
I've never been much of a milk drinker, but I do eat cheese and yogurt on occasion, mostly because I enjoy the taste and I also use a lot of heavy cream for sauces and gravies.
I could live without it if I had to, but I'm not convinced at this point that it's necessary. Moderation may be the key as with many things.