Interesting thread. I don't know the answer as to the differences in the stickers.
I do have a question as well; if GVWR "doesn't matter", then why do manufacturers bother to assign one to vehicles?
Here in BC, GVWR is certainly a number that is enforced. There are random roadside weight checks and if your vehicle is over the GVWR, they have you unhook your RV and you can pick it up from the towing compound with a vehicle that has an adequate GVWR to handle it. Hence one of the major reasons I have a tow vehicle with a 14,000 lb. GVWR and I am well under that number.
I would suspect as time continues with so many people pulling too big of rigs with not enough truck, GVWR will be enforced in other jurisdictions as well.