Some of the poorest traveled from so-called "misery villages" in Argentina's capital, thanks to donations from the Buenos Aires archdiocese. Their agenda at World Youth Day includes meeting with other disadvantaged youngsters in Manguinhos, a favela Pope Francis plans to visit, and sharing stories about Jorge Mario Bergoglio, the subway-riding Argentine Jesuit they now affectionately call their "slum pope."

Road trips can be fun, but many have been expressing more profound emotions, excited by the changes they see in the church since Francis was elected in March. His first months as pope have already renewed their faith, many say, by showing how church leaders can get closer to their people and relate to their real-world problems with humor and a common touch.

"We were concerned after Benedict resigned, but when a Latin American pope emerged, so close to young people, it really changed the situation and our numbers grew. A little while ago we thought that there would be 5,000 Chileans and now we see that 9,100 of us are going, more than double what we expected," said Alonso Molina, the 21-year-old coordinator of a group visiting from Chile's Vicarate of Youthful Hope.
 
Brazil has more Catholics than any other country in the world and its church has struggled to compete with Latin America's vigorous evangelical Christian movements, so it's a logical destination. And while many Argentines were disappointed that Francis didn't choose his native Argentina for his first papal trip outside Italy, they were making the best of it: More than 30,000 Argentines were making the pilgrimage, the largest foreign delegation.

In all, 350,000 young Catholics signed up, similar to previous World Youth Days that later attracted much larger crowds. In any case, Brazilian authorities prepared to receive a million or more visitors during the pope's weeklong stay.

Many Argentines had already planned to attend last year, "but everything got bigger after March 13, with the boom that was generated by the news that the Pope is from our land and our city," said the Rev. Marcelo Miceli, trip coordinator for the Buenos Aires archdiocese.

The diocese channeled contributions and was able to subsidize all-inclusive trips for $500 a person, Miceli said. "We've received a lot of help from the community, many donations. It has generated an incredible wave of solidarity."

AFIP's press office refused to comment on the controversy, which prompted an official public complaint from the church: "We made many appeals to various government agencies, but we have not received official responses about the possibility of changing money," the statement said.

Paraguay doesn't limit currency trading, but poverty is a grim reality for many members of the Catholic church in that country.