I was thinking something similar on my 2012 GMC Sierra 1500. The yellow sticker said 1474 for occupants and cargo. Just about every other Sierra 1500 I heard about was higher than that (granted, I never looked at other door pillars or contacted GM about it). I traded that truck on a RAM 2500 and never worried about it again, but that always stuck in the back of my mind as odd.
Aside from solving the mystery of the number on the sticker, the true number is the GVWR minus the scale weight gives you your remaining payload capacity.
2014 Jay Flight 28 BHBE
2015 RAM 2500 6.4L HEMI, Tradesman 4x4, 3.73
Blue Ox SwayPro (BXW 1503)
Upgraded from an REI internal frame backpack and a Eureka 1/2 dome tent!