"Shake It Up"

When you're a guest in a bachelor's home, have you noticed that when you're offered something to drink, you're given a list of specific beverage options?
Because the bachelor can't afford juice and milk at the same time.
And if you were to visit eight different bachelors in the one day, you'd get eight different combinations.
"Would you like something to drink?
I have chocolate milk, water, and I think there's a can of gingerale that someone ended up not using for mix."
"Can I get you something?
I have apple juice, Pepsi, and some sort of mango, banana orange juice. I don't know where that came from...I think someone was using it for mix."