Similar to a Carpet Bagger, a milk bagger is a person who is hated by the general population, and does change the milk. Said "Milk Bagger" is someone who will drink the rest of the bag of milk, and they will put it back in the fridge. This person must be dealt with by being given the asshat treatment.

the thing that you don’t have when you’re phones percentage is over 20

A girl who drinks the cum out of a man's condom after sex, and then proceeds to saying "Got milk?".

One who voluntarily gives up their own freedom and liberties so they may suck off the teet of the American government from cradle to grave; A follower of the teachings of Karl Marx; a person who believes other tax paying citizens OWE them a hand-out to purchase food, housing, an education, health insurance and other life commodities.)

A slur used against canadian "people" in reference to how they use plastic bags to hold and sell milk in stores.