Coffee shop owner Micah Ooi, 37, often does not mind when patrons occupy a table without ordering any drinks. But it soon became a habit. Customers would come in and order food from the hawker stalls, but not cough up a single sen for a drink.

A popular khao man kai restaurant in Bangkok's Prachachuen area has come under a storm of Facebook anger after it secretly took photos of its patrons and posted them on its Facebook wall with insulting comments.