Boston’s transit authority, the MBTA, shuts down the subway system around midnight. Businesses (including restaurants, bars, and dance clubs) don’t close in Boston until 2 am. There used to be a "night owl" bus service that (barely) supplemented the T on Friday and Saturday nights from midnight until 2. Now you should just drive drunk, I guess. And of course people with service-sector jobs had just better be able to afford to own a car or take taxis.