Venezuelans were among the top visitors to the US in 2011, which is not surprising at all.
On this chart you can see the top visitors to the United States for last year. Sources come from here and here. I reordered them by tourist per inhabitant. That is: I divided the number of tourists from country X by the population of said country X.
More than half the Canadians went to the US in 2011. That is not astonishing, considering that most Canadians live less than 70 kilometres from the USA border and they can freeze to death if they travel rather to the north. Mexicans are less likely to visit their pals but almost every second Mexican city visit his gringo neighbours last year. Britons love their former colony and Australians are also have an intense relationship with the USA, so they are also among the most loyal visitors to that country. Then you see the rich Dutch, the also very rich Japanese, the still wealthy South Koreans, French, Germans...and Venezuelans.
Venezuelans are more likely to visit the US than Brazilians, even if Brazilians have a higher income per capita than Venezuelans. You can say Brazil looks rather to the South and you will have a point there. Brazilians inundated Argentina. But Brazil has also kept stronger links to Europe throughout the decades. Brazil's population hubs are mostly very far to the South. Venezuela's bigger cities all face to the Caribbean. I reckon Venezuela's government ain't happy with that.
The current Venezuelan regime imposed a strict currency control back in 2003 and it has become tighter: a Venezuelan citizen can only get so much in foreign currency per year for tourism. She has to prove her expenses by showing every single purchase bill if requested. This and many other things in Venezuela's subsidized economy have led to a huge black market. Venezuelans - the privileged revolutionaries or majunches alike - keep buying dollars and euros in that black market because they don't know when the bubble will burst but they do know it will. That is why many Venezuelan tourists also use their trip to the US to open a US account or to take with them as many dollars as they can to their old US accounts.
One of Chávez's honchos, former Acción Democrática, former Causa Radical politician and now PSUV leader Aristóbulo Isturiz once said the Chávez government couldn't do without the currency control because "it would fall right away". And sure it would...even if the country does need to do it...it is this currency control that keeps a powerful elite - left and right - becoming immensely rich at the cost of María González with her 6 kids in Maturín or Guanare.