Around 11:30 a.m. on a muggy July Wednesday in Midtown Manhattan, the line for Uncle Gussy’s food truck started to form.As the truck served warm gyros and fragrant chicken platters to the customers who wandered out of the sleek office towers nearby, Nicko Karagiorgos, the food cart’s gregarious co-owner, greeted his regulars. How are the kids? Did your friends like the food last time?But soon, he got to his real questions: When is your office reopening fully? When are the workers returning?For Mr. Karagiorgos and thousands of other food trucks and vendors in New York …
