The kitchen was used because it was generally the largest room in the house. All the furniture would be removed —including the stove in summer —and the fiddler would be placed out of harm’s way, maybe in a doorway or even the sink." -New England Fiddles.
"The men chipped in to pay the fiddler, and the women brought the lunch—sandwiches, cake and coffee. After barn chores, around 9, everyone arrived and threw their coats onto a bed, which usually also had a few sleeping children on it... The dancers filled the kitchen, and sometimes spread out into other rooms, dancing until way past midnight, when they would pile back into their sleighs for the ride home." -via Old Stone House
A few years ago I picked up a fantastic documentary (on VHS no less) called The Unbroken Circle which traces traditional and country (not C&W) music in Vermont, from radio cowboy bands to contemporary square dancing and callers. The producers followed up by releasing a great cd, Kitchen Tunks.
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The selections reflect Vermont's Yankee and French-Canadian traditions as well as the impact of Southern styles and popular music... fiddlers, harmonica, sing songs ranging from childrens ditties to comic tales to hymns, whistling, a foot-operated piano "rig," and square-dance calls.
Listen here. (try 37, 39, 40, and 11, 12, 13)
More on kitchen tunks in the Dictionary of American Regional English (killer resource btw).