Remember that chapter in Freakonomics called "Why Do Drug Dealers Still Live with Their Moms?" On the basis of sociologist Sudhir Venkatesh's work with a Chicago gang, Dubner and Levitt explain that crime does not pay much for street-level drug traffickers.
The same does not seem to be true in Brazil. An article in today's Estadão tells the story of two young women who used to sell drugs in the streets of Cidade de Deus, the favela made famous by the eponymous movie. They now collaborate with the Unidades de Polícia Pacificadora (UPP), which the state of Rio is implanting in the favelas from which it expels traffickers. Apparently happy with the change, they nonetheless point out that they miss the 2000-3000 Reais they used to make weekly, peddling drugs.
Now, this is a lot of money: between 1200 and 1800 US dollars per week, or roughly between U$60,000 and U$90,000 a year, this in a neighbourhood where, according to a recent study by the Federation of Industries of Rio, the average family makes less than U$400 (R$648) per month, or about U$4600 per year.
Obviously, the two young ladies may have been boasting, but clearly, the incentive structure in favelas such as this one is still tweaked massively towards crime.