They were domineering and often collected stall fees in the market at the docks. Although it was said that it was stall fees, that was actually self-proclaimed. They maintained the order here and chased away the troublemakers. They also prevented outsiders from stealing, so they wanted the vendors to give them money.
There was no fixed time. They would come whenever they were in a good mood.
Many vendors did not pay. If they were lucky and the other party had money at that time, things would go unnoticed. If they were unlucky, they would be deemed as 'foreign villains' and be punished. After that, the group would quickly slip away and say that if they wanted to sue them to the officials, it would be useless as they had their own forces to protect them.
There was no choice.
Over time, this group of people became the hegemon of the docks and market.