IF YOU HAPPENED to find yourself in Portland, Maine, on Friday, July 18, you might have noticed a curious influx of visitors: couples in their 40s—the men in slick athleisure, the women wearing designer sunglasses—passing through the lobby of the Press Hotel and eating meals at Scales, a select seafood restaurant on the waterfront. They traveled from places like the Upper East Side and Chappaqua. They all seemed to know one another. The dads congregated in hotel bars. The moms had flawless manicures.
On Saturday morning at 7 a.m., they piled into their cars—Escalades, Rivians, G-Wagons—to drive north on the highway, eventually turning onto dusty, bumpy wooded roads, passing signs with names like Camp Vega, Camp Takajo, Camp Mataponi, Camp Laurel, Camp Androscoggin, Camp Matoaka, and Tripp Lake Camp. Once…