The reason you see many sites post the "dry weight" of a camera in the specifications table is because that is the information that is provided from the manufactures. All of the "Specs" data is provided from them. We don't actually measure or weigh the camera to get those figures.
Some manufactures do list the weight including the battery and memory card, but that is not the norm.
On our site, we always make a note at the bottom of the specs table stating: Specifications as represented by the manufacture.
I hope this answers your question.