It's initial popularity was apparently through SE asian "ethnic" restaurants catering to immigrants too, it seems like?
But yeah, in the end we like what we like -- I'm a non-immigrant American, I definitely liked the huy fong one the first time I tried it (in the mid-90s?), and still do, and I'm not ashamed regardless of how "authentic" it is. :)
But yeah, in the end we like what we like -- I'm a non-immigrant American, I definitely liked the huy fong one the first time I tried it (in the mid-90s?), and still do, and I'm not ashamed regardless of how "authentic" it is. :)