You are 50 years behind. The US Sugar Act was eliminated sometime in the late 70s. We do not pay more than the world for sugar except for the heavily subsidized European sugar. Additionally, the US pays more for foreign sugar to those nations who have IMF money guaranteed by the US. In addition to government rules and regulations, EPA, OSHA, etc impose costly restrictions on US sugar producers not imposed on foreign producers. Nobody tests foreign sugar imported to the US for prohibited herbicides / pesticides. We do not know nor have any control of agronomic practices outside the US.
See what the Cato Institute has to say about U.S. sugar policy.
http://www.cato.org/pubs/tbp/tbp-013.pdf