I don't know if they still do
[QUOTE=Tres3;435131]If you buy your ticket at the downtown office, you can pay cash in pesos and take advantage of the exchange rate. If you buy online with a credit card that is denominated in dollars, you will receive the official rate, less whatever the credit card company charges. Some credit cards are pretty onerous. They charge both a currency conversion fee and a foreign transaction fee.
Tres3.[/QUOTE]But the price also used to be higher online. Higher price + (fucked exchanged rate X fees from your CC company). Convenience of doing it online=Going to the ticket office and buying there. (For me).