Why Did a Train Carrying Biofuel Cross the Border 24 Times and Never Unload?

"A cargo train filled with biofuels crossed the border between the US and Canada 24 times between the 15th of June and the 28th of June 2010; not once did it unload its cargo, yet it still earned millions of dollars."  Thanks to the wonderful incentives and subsidies paid for with your hard-earned money.