No you are wrong. The long and the short of it is that ATT is paying $699 for EVERY 32GB phone. Tax on $699 must be paid no matter HOW much they sell it to you for. If they GAVE it to you for free guess what? You would still have to pay tax on the $699. This is how it has ALWAYS worked with subsidies.
When you NEGOTIATE a lower price on a car, you did just that. You didn't receive a subsidy. With your logic someone could GIVE you a million dollar house and you would argue that you should not ever have to pay the yearly property tax? Get real.