Pretty much every recipe I've seen for cheese fondue includes either white wine (sometimes alongside kirsch/brandy) or some kind of beer in the delicious cheesy sauce.
Why is the added liquid (seemingly) always alcoholic - as opposed to adding, say, water? Is it because beer or wine complements the other flavors in the fondue, or because milk proteins are alcohol soluble so it achieves the desired consistency? Or is there some other reason that combines those two explanations (or presents a different one entirely)?