Historical, predating LGBTQ sexual identities & contemporary community; archaic slang.
From the slang word trade.
A alpha masculine heterosexual identified blue collar man who disdainfully allowed submissive men (aka fairies, pansies, fags & queers) in a receptive role to sexual service him. Those willing to "risk" being roughed up & suffering verbal humiliation & degradation during the sexual encounter. As well as the "risk" of being robbed or subjected to demands of money afterwords.
"What happened to your face? Did you have sex with some rough trade guy last night?"
A common laborer, typically of a disheveled or frumpish appearance, usually unsettled and rarely living in one place for too long; Often associated with drifters, hobos and other societal outcasts.
"My dad hired some rough tradesman down at home depot to help him install the new gutters on the house."
Dirty poor white trash or rednecks who want a good blow job but have a macho nature about them that says no; may or may not rough up the giver just a bit.
Sandy preferred rough trade when he was horny and wanted to give somebody a blow job. He liked being called names and getting slapped around. He also liked smegma.
Indie label; originated in the early 80s for post punk bands such as Gang of Four, Delta 5.
Now home to the strokes, moldy peaches, libertines, hidden cameras etc.