I wouldn’t say it’s common, but I also wouldn’t say it’s unheard of…and I would never put it past Americans to try an odd condiment application.
Honestly though, when you look at the ingredients, it’s not too drastically far off from the ingredients of a sauce you might specifically put together as part of a more traditional rice dish: tomatoes, vinegar, onion, garlic, ginger, coriander, cumin… bit heavy on the sugar but a lot of sauces in Asian cooking are even sweeter.
I agree it seems repulsive on the surface to me too, but now that I’ve been thinking about it…I kinda wanna try it.