2017 Buick Encore Preferred AWD - Need help understanding the quote

I tried to see if there anything interesting around year end to put together for my mom.
Got a quote shown below as a screen shot
New photo by Slava Lysenko
The biggest question is what the heck are the taxes in box 16 in the amount of $2,689. Everything is happening in CT state - car registration, dealership location - so why taxes? We are as far as I know a state where only payment gets taxes.
Is anyone familiar with this screen for Buick/GM financial to give an explanation so when I go back I can have a good answer other than “what the heck is this?”

Thank you,
Slava

Bump. Anyone? 202020