Every place in Vegas has a gimmick. At this ’50s-style rock ‘n’ roll diner, servers drop everything to perform song-and-dance numbers straight out of Grease. It’s hilarious fun, but it sure does slow service down. Copious comfort food tastes just about right for the prices. Blue-plate specials won’t leave you hungry, and super-thick milkshakes come with silver sidecars, just like when you were a kid.