I reckon that the average gangster just wants an artificially easy life at the expense of others. A bit of prostitution, narcotics, gambling, theft at ports, and extortion of small business and you are done. Child trafficking takes it to a different level of brutality and social unacceptability, thus risk and effort. You can see how a “survival of the filthiest” rivalrous competition might emerge. Only the most depraved and ruthless evil eventually prevails. The pattern is the same even if you escalate to fighting AI systems from alien realms.