At least that's what Thailand's IP Authority explained to the public. Many Thai people are outraged of what they saw as a "ripoff" of sauce (purportedly) made in Sriracha, but marketed by foreign companies. The authority did suggest a geographical indicator (GI) as a way to market it as genuinely coming from Sriracha, but AFAIK, there hasn't been a proof about the distinctive property of sauce from Sriracha, so it hasn't yet been recognized as a GI.