When you have a unique service that nobody else offers, you must advertise it. When you do not have a service that everybody else offers, must you advertise it? Indeed, you must! At this hostel in Shenyang, there is a striking sign: "This is a proper hostel which operates according to the law. [no Misses]. Please do not interrupt our rest)." Obviously, every other hostel, motel or hotel in the same neighborhood has many Misses. [sina]