Huh?
The Dealer assigned the finance contract to the Bank. While a finance charge is charged on the total cost, including the sales tax, the Dealer will get none of it. The Bank will make a small interest rate (whatever your APR is) on the $2,000 for 36 months. Yes, the Dealership might get a small referral fee from the Bank for assigning the deal to the Bank, which is not always the case, but I imagine the "additional bucket of money" and "pure profit" you refer to is probably less than a few hundred dollars, if anything.
As to your second point, the Dealer doesn't pay the taxes, the Dealer (like every other retailer) collects the taxes and transmits them to the State. Its like saying the sales tax on a six pack of beer is pure profit for the grocery store.
As to your third point, that you are banking that the Bank will not want the actual title is also wrong. The Bank just made an unsecured loan at a lower interest rate than is customary in comparison to a secured loan, and the Bank is out of compliance with the Federal Reserve (if a National Bank) or a State Financial Board (if a State Bank). Banks charge way more for unsecured loans (if they even make them, most don't) than secured loans; and Banks have guidelines with the Federal Reserve which govern their interest rates. These internal rules will compel them to call a default on the loan and ding your credit back to 500. So now, your unwillingness to pay the taxes makes the Bank's loan non-compliant with their regulatory agencies once they find out, and they will when the Bank doesn't get the Title. Heck, the Dealership is now in trouble with the Bank, and will likely rat you out within a matter of days.
You don't seem to understand how this process works, which might be good for you, because you can play dumb.
Yeah, hire a lawyer. Let us know what his retainer is. I'll bet you a cookie with a fat raisin in it that the lawyer's retainer is more than the $2,000. Yeah, whatever you do, don't talk to the Dealership, don't be nice, be a jerk, refuse to pay the taxes, don't cooperate with the Bank, and let the Lawyer handle everything. You've done all the internet research, and now know everything. Let us know how it works out.