Mayor Bloomberg

As we mark the official start of summer this weekend, like in years past, many storefronts from Rodeo Drive to Fifth Avenue to London’s West End will open up their doors, offering cool, air-conditioned oases from the sweltering heat of the streets. Yet, what serves as a clever marketing ploy for the businesses—often successfully luring in helpless passersby first for the cool and then keeping them there for their wares—is also, as you might imagine, a huge waste of energy.

Randy Cohen, the man who sorts out readers' ethical dilemmas in his NY Times Magazine feature column The Ethicist , weighs in on the automobile's impact on urban life.