Vendors drive traffic but rev up operator aggression

When Kenny Lao began selling his restaurant’s dumplings out of a converted postal truck last September, he didn’t anticipate that competitors would threaten his life because they felt he was encroaching on their territory.

Lao, who co-founded the trendy Rickshaw Dumpling Bar restaurant in the Flatiron neighborhood of Manhattan, also didn’t realize the difficulty he’d encounter finding a mobile vendor permit in a city that doesn