I call it a battery discharger.
A $600 USD gimmick, it seems.
Seems the price differential between the 2 port TB-3 13" and the 4 port TB-3 13" w\ Touch Bar & Touch ID is $300 USD.
If I'm not mistaken. I went o_O … Seems steep. Please correct me if I'm wrong.
The model with the touchbar also has a faster CPU, I guess some of the price difference is due to that.
Your hands don't have to move around as much to select a toolbar item and you don't have to move your hands up to the screen like a surface. I think the touch bar will be great for productivity.
A gimmick.