When Su Beng's plot to assassinate Chiang Kai-Shek was discovered in 1952, he was forced to escape out of martial law era Taiwan by stowing away in a ship exporting bananas to Japan. Though he survived the 5 day trip, and got safely off and away from the boat, he was later arrested for illegally entering the country.
After serving about 3-4 months, in a Kobe detention center, Su Beng was to be repatriated to Taiwan. But somehow "fate intervened" and when Su Beng was released, he was surprised to learn that he had been granted asylum in Japan. Suddenly he had to figure out how he'd make ends meet in post-World War II Japan, which was in shambles. However he was to make a living, he first vowed that he would continue his work for the cause of Taiwan. This meant that he'd need to have the means and flexibility to do so. Having been educated in Japan (at Waseda University), it would have been relatively easy for him to find a job, but he decided that instead of being under someone else's employ, it would be be best to work for himself.
At the time, many of the Taiwanese in Japan had opened up pachinko parlors, which had proven to be highly profitable. Pachinko machines are pinball-like machines used for amusement and gambling. When this was suggested as a "business proposition" to Su Beng, he rejected the idea. Not only was he looking for a way to earn a living, but for a way to fund the fight for Taiwan's independence, and to him it somehow didn't seem right to use gambling profits to fund the cause.