Apparently unmarried men staged a \"protest\" on Shanghai\'s Metro on Tuesday, wrapping themselves in quilts with a sign round their necks saying \"we want wives.\" The protest attracted media attention but Shanghai Daily has discovered it was a publicity stunt apparently planned by a quilt company. The stunt was exposed by the bachelors\' contact details, which led to the quilt company. The company in question was also the first to publish the photographs on its website. It refused to comment yesterday. This is just one example of a growing trend of using the subway to promote products and services. In August, several female passengers stripped to their underwear in a subway train, constantly changing their clothing to the embarrassment of other passengers. The following day, as hundreds of passengers swarmed onto a Metro Line 2 train, they found it had been transformed into a clothing shop, with clothes hanging from the railings and free to take away. The incident caused chaos and was stopped by Metro police. E-commerce giant Taobao admitted it organized the stunt. In July, a woman dressed in period Chinese costume was found \"begging\" at a Metro station, not for money but asking people to \"take her back to ancient times.\" The woman produced a marketing certificate showing she was affiliated to an online game operator. Other stunts include men and women dressed in cartoon costumes, branded clothing, and even pajamas, promoting big brand names. As long as they do not disturb public order, their behavior is regarded as \"personal acts\" and ignored by Metro operators. A Metro police officer surnamed Zhou said that companies and individuals have to apply to Metro operators before holding events in carriages, and the operators will consult the police to assess the potential consequences. She said some companies launched events without informing them and they were penalized if the events cause serious consequences. In reality, however, Taobao might be the only company punished by police for clothing shows dressed up as artistic events. Taobao planners have been cautioned for disturbing public order, while other promoters, including the suspect quilt company, may walk away unpunished as their deeds are regarded as \"unharmful personal acts.\" But the difficulty in imposing penalties is encouraging companies and individuals to plan publicity stunts, a Shanghai Daily investigation has found. Newspaper advertising may cost a company tens of thousands of yuan daily, while promotional stunts disguised as \"performance art\" may cost only several hundred yuan hiring staff and preparing costumes. The public become engaged with well-planned events, but are angry when they find out they have been deceived. \"Those dirty tricks. No wonder the bachelors can never find a woman,\" said a netizen commenting on the latest case.