Opium was so significant here, there was even a museum for it.
Historically speaking, poppies were grown here for their seeds which then would produce heroin. People were making money but not in a good way. In the early days, people had already got addicted to drugs and some were involved in illegal activities and all sorts of related crime. As a consequence, Thailand government had taken drastic action such as prohibiting people from planting poppies anymore.
Read more about the interesting history of opium in Thailand and the Golden Triangle HERE.