> the waspy country clubs are mostly staffed with townies and a lower representation of immigrants than comparable occupations for different employers in the same towns

I've played tennis and golf all over Westchester County, all over Fairfield County, and in Long Island. On the golf side, yeah, it's townies. Same goes for pro shop, tennis assistants, pool staff, and sometimes, kitchen/snack bar staff. But the folks who mow the lawns, clean the locker rooms and toilets, water the greens? Hell no those aren't locals.