The owner of a Massachusetts ice cream parlor closed its doors just one day after reopening amid the coronavirus pandemic in response to how angry customers mistreated a teenage employee. Mark Lawrence, who for 19 years has operated Polar Cave Ice Cream Parlour (in Mashpee) waited to reopen his shop under the state’s restaurant guidelines until Mother’s Day weekend. But Friday’s grand reopening turned into a harsh lesson for the small business. Lawrence said that customers frustrated with having to wait longer for their ice cream after the shop grew busy took their anger out on his staff. He said one of his best workers quit and the words used by some customers “you wouldn’t even say in a men’s locker room. And to say it to a 17-year-old kid, they should be ashamed of themselves.”