That would be outright illegal. It's more likely that op lives in lower humidity areas and non air tight food looses some water weight, or that op needs to calibrate their scale or buy a new one.
Yeah, uh… you realize there are net weight tolerances, right? Companies aren’t expected to get exactly the same weight for every single item they put out. And it’s not really possible for certain products.
Op is talking like everything he weighs is shorted. The tolerances you speak of mean that sometimes you're a bit over, and sometimes you're a bit under.
But if my 40 pack of pizza rolls stops at 39, ima riot.
So I eat a pizza roll or two here and there. I pack most of the bags full. And besides — they’re delicious. A man’s gotta eat. 39’s close to 40. 38, 37 at worst. You’re not gonna see a bag coming off my line with less than the full 36 let me tell you.