The food cart scofflaws who entice concertgoers with sizzling but possibly unsanitary street meats are back on a roll – and a bun! – in Clark County, officials say. The county’s public health department reports that unpermitted vendors, who are transported en masse by vans with out-of-state plates, started popping up in the parking lots surrounding the RV Inn Style Resorts Amphitheater in Ridgefield last month. They’ve been spotted at least four times, according to a spokesperson.