WordNet (r) 3.0 (2006):

snack bar
    n 1: usually inexpensive bar [syn: snack bar, snack counter,
         buffet]

Moby Thesaurus II by Grady Ward, 1.0:

46 Moby Thesaurus words for "snack bar":
   automat, beanery, bistro, buffet, buvette, cafe, cafeteria,
   canteen, cantina, chophouse, chuck wagon, coffee shop, coffeehouse,
   coffeeroom, cookhouse, cookshack, cookshop, diner, dining hall,
   dining room, dog wagon, drive-in, drive-in restaurant, eatery,
   eating house, fast-food chain, grill, grillroom, hamburger stand,
   hash, hash house, hashery, hot-dog stand, kitchen, lunch counter,
   lunch wagon, luncheonette, lunchroom, mess hall, pizzeria,
   quick-lunch counter, restaurant, smorgasbord, tavern, tearoom,
   trattoria