Why are Colombian bananas crooked?

There's a lot of evidence that show that banana companies paid paramilitaries in the past armed conflict. The same companies are the main exporters to Belgium. Activists also claim that those companies are still buying bananas from conflict areas where deforestation, illegal land occupations and paramilitary terror are frequent. Conditions on the plantations are problematic, as workers complain about an unworthy existence. Certificates, international conventions and guidelines do not seem sufficient to guarantee us that the bananas from Colombia are not too crooked.