The current King and Queen prefer this it seems, and have taken steps to allow criminal activities flourish in this city. For two reasons, it provides extra profit to the current monarch in his constant struggle against the other nobles, and it keeps the rest of the planet rather free of outsiders. One of the actions taken to promote these activities is the yearly celebration Commerce Day. On this day every standard year, all taxes are suspended on the trade coming in or out of the city-state. All contraband item laws are also suspended, and on this day you can see people selling glitterstim spice out in the open.
Of course this influx of criminal activity only helps to hinder relations between the current monarch and the other nobles, who often band together to try and usurp the King or Queen. Because of this, a major import to Wistril is mercenaries. From all over the sector they come, to provide services for one noble or another often in exchange for weapons that are so plentiful here due to the thriving weapons factories.