In Germany they legalized prostitution just in time for the 2006 World Cup held there. So that the legal, regulated, over 18 prostitution was offered in large and efficient amounts enough to make it not worth for any bad pimp to force any girl, young or old, into streets hooking. This not only let bankrupt and give-up the illegal pimps, but also brings a few billion euro of extra tax to government.
When a World Cup it happens in Brazil, they got bad prostitution issue anyway when no event was there, all years since the country is inhabitated, so bad prostitution simply grows as an "opportunity" with an event like this. The Brazil politicians it was unable and/or willing to make the country's living standard as good as the one of USA or Germany, and so the Brazil politicians are to blame for this situation, not so much the foreign customers. Where is the mention about Brazil politics failed to give alternatives or support to those people who got nothing better than end up this way, just because born there?
About journalists, there's the World Cup so they go care what happens there, but to be cynical, at least this event may bring some extra cash to the people involved, more than the average pre and after World Cup, when the life of those people may be more miserable! When less foreigners, prices lower and less cash... illegal, but it is still cash, that the BR government does not provide to support own poor population, who got nothing better to do than to beg foreigners.
To Journalists focusing on rich foreigners being customers of forced prostitution, I would remind those places such as Bangladesh, where forced prostitution is much worst and less paid than Brazil, because no foreigners or events. Only local people are customers, see an extract from Whore's Glory (I advise everyone in GFY to watch):
http://www.imdb.com/title/tt1327628/
Girls in brothels of Bangladesh are as young as 11, taking some cheap drugs to stay up and appear more round. Can never exit the brothel for whole life (this is more strict than in Brazil), and are paid a few cents only (some 1/10th of cheapest one in Brazil). There's no World Cup or foreigners to blame, it is pretty accepted by local government and relition. Interviewed people say: since here the women can't have sex before of marriage (all must marry virgin or so), then if there was not the brothel with whores (no one will marry), people would rape random girls all the time (rape there is not that a big crime, but there's death penalty if a wife betrays the husband).