"Shen Bao" played an important role and helped form public opinion at the end of the 19th century. The paper ran a campaign against hiring young women as waitresses in opium dens. According to the campaign, this made it difficult to distinguish between what could be tolerated, and what could not, because it implicitly said these women would also provide sex services in the dens. Most of the dens with this practice were in the French Concession. The campaign said that one of the reasons this problem existed was that there were foreigners in Shanghai. There was an uproar, and the practice was banned; in reality little was done to eradicate it, though.