New York, July 18 - With chain stores sprouting all over town, New York City is getting more and more suburban in character. So when a yellow school bus stopped on a midtown street last night, and disgorged a horde of Little League baseball players in uniform, we figured the city had just gotten too squeaky clean for its own good. But this slice of small town Americana had a big city twist: the giggly kids were actors, and this was the premiere of Bad News Bears. Even the supposedly darkly quirky Billy Bob Thornton was amiable, smiling and chatting, and all of his costars claimed that he's down to earth, funny and nice. We looked in vain for a vial of blood around his neck. The original Bear, Tatum O'Neal, who, like NYC, has cleaned up her act, was there for a touch of nostalgia. We're off to the mall for some excitement.