In 2001, I did a month long exchange program to Thailand. A group of eight Canadians stayed with eight Thais, and the year before they stayed with us. Incredible program.
All the Thais, as you mention, had nicknames. But many of the nicknames were English words that weren't really used as names in the West. I lived with a guy named 'Knight'. Another guy was 'Farm'.
Were these names Anglicized versions of Thai nicknames? Or were the actual nicknames just sometimes pulled at random from an English dictionary?