Unfortunately small companies do not always have a scale to weigh a pallet. Therefore they weigh a part and multiple by total pieces shipped. Or weigh one box of parts and multiple by total boxes. And guess at empty pallet weight.
This method does not take into account packaging and wrap and banding. If they ship 600 lbs of “parts” the can easily have 10% more in dunnage along with “parts”.
I had one customer that I went into daily, and got to know guys very well, they switched software that was supposed to be latest and greatest for manufacturing companies to keep inventory low and never run out of material for orders.
The shipping documents were created on what customer ordered, in pounds. The software did not take into consideration pallet weight or shrink wrap.
Shipping guys called them out, told them trucking companies bill by weight hauled, they were told “ we bill customer by what we sell not what is hauled.
The fancy program was not designed to have
Dunnage figured into documents because that would mess up how material was ordered.
Needless to say not every shipper has accurate method to weigh, but company pretty much weights every thing the same.
Unless you get the shipments mixed up on your lift and weigh a skid of mirrors and not a skid of popcorn.