Madonna's concerts out sell Lady Gaga's 3 to 1 in South America. Madonna's 'MDNA' tour tickets are three times more expensive than Gaga's 'Born This Way' tour tickets. Plus Gaga's management offers buy-one-get-one-free deals to fans. The 'Examiner' reports that the 'Bad Romance' singer played in front of a crowd of 50-thousand people, but only 17-thousand tickets were sold. Meanwhile, Madonna was able to sell the same venue without providing incentives.