When I was a kid and we visited my grandmother in her Chicago high-rise, I was amazed that the concierge recognized and greeted us by name the moment we stepped

When I was a kid and we visited my grandmother in her Chicago high-rise, I was amazed that the concierge recognized and greeted us by name the moment we stepped into the vestibule. To memorize not only each resident's name and face, but also those of their occasional out-of-town guests, is quite a feat.