Is there a phrase in English that works as a direct antonym to the idiomatic carriage trade, that is, the wealthy patrons of a store, restaurant, hotel, etc.; the elite clientele?
carriage trade: [mass noun] North American informal The wealthy clientele of a business: determined to pursue the carriage trade, she quickly established an old-girl network (Source: ODO)
carriage: A wheeled vehicle, especially a four-wheeled horse-drawn passenger vehicle, often of an elegant design. (Source: AHD)