EVERETT, Wash.—Less than a dozen cars speckled the parking lot outside the White Elephant Bar and Grill on a recent Saturday night in this growing Seattle suburb. Inside, most booths and tables sat empty while two electronic dart boards hung unused on the side wall. A handful of customers encircled the restaurant's lone pool table, sipping beers and conversing easily at normal volume levels. Owners John and Donna Kerns leaned on the end of a deserted bar and watched helplessly as their once buzzing establishment choked to a slow death on its clean, smoke-free air. So it is for thousands...