Do you mean the packaging is weighed along with the meat, or that the weight of the packaging is not included in the weight of the product?
Tare means to zero out the packing...........
In the meat department i worked at as a young guy…you put the package on, reset the scale and then weighed the meat. If you are using absorbing pads and the meat is sitting for a couple days, that pad is going to gain all that moisture weight coming out of the meat.
You are usually always better buying meat cut at the counter. It’s fresher and the weigh it right in front of you.
The stuff in the case has been sitting for about a day longer at minimum.
The tray and the pad should be put on the scale and then tared to zero. Then add the meat until the weight matches the label claim. Including the weight of the tray and the pad in the total weight is cheating the customer. It’s not by much, but it adds up.
The scale gets a tare weight entry, which is deducted from the total.