I live in Sao Paulo, Brazil. Why can we get surface economy mail subscriptions in South America?
Early on we did offer subscriptions to South and Central America by both Surface and Airmail rates, but found that approximately one-in-four magazines sent by Surface Rates to Brazil, Argentina, Chile, Cuba & Venezuela would never arrive at their destination, requiring a second copy to be sent. Because of those early experiences, somewhere around issue 7 or 8 we decided that all non-USA destinations in the western hemisphere would be serviced by air-mail only.