I am not talking about carrying a weapon in a car. I am talking about mounting one on top of the vehicle to be used while driving it. This is the better analogy to the drone in the article.
As awesome as it would be to have a belt-fed .50 on top of a truck... I think it should be illegal on public roadways, as there is no possible legal way to use it.
Now, if the vehicle is on private land out of sight (and range) of the public... go for it! I bet you could charge a fee and get some thrill seekers to have fun with it. As for transporting the weaponized vehicle from point A to point B... you would either need to store the vehicle in a trailer or disassemble the weapon from it.
I am sure there are more caveats that I have not thought of, but this is what makes sense to me.