It’s good they specified sugar as sugar substitutes have wildly different densities. Imagine the confusion if they said “sweetener!” That’s the sort of stuff that makes space missions fail.
One wonders if the packets were US specification (a precise 2 - 4 grams) or the much looser Polish designation (5 - 10 grams). It's critical to get to the bottom of this: what is the SI standard for sugar sachet?