While the career has always existed, it was outlawed in many places throughout history. In 2525, it was legal on the planet Gilgamesh. In 2552, there were "slut chat" chatter sex businesses active on Earth.
During the 23rd Age of Doubt, sexual services were sold to San'Shyuum who were on the Roll of Celibates and were not permitted to breed. Around the human year 2552, Jiralhanae also owned brothels on their moon Teash.