As a milk lover even i have to admit, as long as you are eating the right stuff there is nothing you will miss from milk, in fact too much milk is bad for you. As someone else said adult humans and many other animals are lactose intolerant though it doesn't always display in the "typical" way (getting blocked up or getting runs) it takes its toll elsewhere as every body is different.

Also, unless you can get milk from a local source that you have seen in operation you can bet hands down the milk is unethically sourced. The demand far outweighs the supply and the cows are the ones that feel the pinch , not just our wallets. You will hear people say that some cows (especially Holstein) enjoy being milked but you have to take into account that even cows not treated with growth hormone have been selectively bred for their udders and milk production. Holsteins even NEED to be milked twice a day due to engorgement. If you have ever lactated you know the feeling of full breasts, imagine that hanging from your midsection carrying another pound or two of excess weight while attempting to walk on all fours. The only good milk comes from family milkers who are treated like family, and not milked to the point of exhaustion or stressed by the removal of their offspring. Different breeds yield different amounts of milk with different fat contents whos milk is best for different byproducts. My SO and myself plan on getting a jersey or a Hyland cow eventually.

Remember that your wallet is the path to change, every family that grows at least a portion of what they consume takes power away from big businesses, even agribusiness. The consumer can force the producer to turn over more healthful, environmentally sound crop/livestock through being selective on who to support with their purchases.

Store milk?