You may be correct when you state most state laws don't require supplemental braking under 3000 lbs, BUT.........
the additional weight of your Jeep, even if it is under, will not be something you'll want to add to the equation if Bert & Ethel pull a bone head move and pull in front of you!!!!!!
I've driven back and forth from Ontario to Florida several times, and IF you look far enough ahead, and Bert & Ethel aren't on the road with you, I've done the trip without the Brake Buddy kicking in to assist. There have been times when the traffic lights play their game, and I'me glad it was there. And.........if you were unfortunate enough to have an accident while you have a toad, I'm sure the insurance companies will do their best not to "back you up" if they feel the situation could have been avoided.
Better to be safe than sorry.........my two cents!
Ken and Terry
2010 Georgetown 330TS being pushed by our
2017 GMC Terrain toad (4 wheels down)