The Federal Government and it's regulations are the funny ones in this case and made Toyota do it! IMO, common sense regulating would have put a limit of some sort like over +20-25 lbs or something on the law.
S10.1 If weight exceeding the lesser of 1.5 percent of GVWR or 45.4 kg (100 pounds) is added to a vehicle between final vehicle certification and first retail sale of the vehicle, the vehicle capacity weight values on the placard required by S4.3 or S4.3.5 and the load carrying capacity weight values on the RV load carrying capacity labels (Figures 3 and 4) required by S9.3 must be corrected using one or a combination of the following methods:
Harper,
Not that I am a fan of most Fed Regs, in this case the Reg you posted seems to have that common sense limit. In our case, according to the reg, if there was enough weight to exceed (the lessor of) 1.5% of our GVWR ( in my case according to the sticker 6300 lbs or 1.5% x 6300 =94.5 lbs) or 100 Lbs, then no additional sticker was needed. (I got that bright ugly sticker, came off the first day).
Why Toyota still puts on a sticker if the add on's at the dock are under that amount? Overabundance of caution I suspect. Not a bad thing.
Be safe.