If that was the case why would he agree to walk and lose that $6 mil? He was let go b/c he wants a long term deal and he obviously thinks he can get more than $6 mil.
Dude NY has the highest State Income Tax rate in the country. Florida has no State Income Tax. What you're missing is, he could probably sign a long term/less money deal in Florida and still walk away with more after tax dollars.
Plus he LOVES Penny!