Nah................. were all aliens made of stardust is the definitive answer here. People get very hung up on race.

World Directory of Minorities and Indigenous Peoples - Thailand : Chinese

In the 1930s and 1940s, various laws and other measures excluded members of the Chinese minority from about 27 different professions, nationalized some areas of the economy or brought it under strict government control – and outside of Chinese hands. Teaching in Chinese was either prohibited or only allowed in private schools for a limited number of hours. Many Chinese either chose to leave the country, migrating to other parts of Asia, or tried to 'disappear' by adopting Thai names so as to be less conspicuous. The creation of state-owned industries, placed in Thai hands, forced the Chinese community to diversify its economic activities and form alliances with powerful Thais.

Why the above happened and what happened afterwards is an interesting story. Someone else can tell it.