Copenhagen climate summit calls for abstinence-free sex workers to protest

The global climate summit in Copenhagen, that's good, but the city of Copenhagen did a really nice thing. What is it? It sounds very funny, saying that they distributed postcards to the hotels of the delegates during this period, and this postcard was not an advertisement, nor was it anything to promote the humanistic characteristics of Copenhagen or Denmark, but it said "Be sustainable: don't buy sex" (hold on: Do not visit prostitutes), and a card instructing hotel operators not to provide attendees with access to sex workers.