> your typical kitchen scale is actually precise to then nearest gram at best

Do you mean accuracy or precision? If you get the same measurement from the same scale twice, that’s precision. However, it might not be accurate.

https://en.wikipedia.org/wiki/Accuracy_and_precision

Good points. I mean both! I have a German Soehnle scale, supposedly a good, old reliable brand, that randomly fluctuates between +1 and -1 grams while it's just sitting there.