The game had to be shipped to manufacturers, and to MS and Sony for certification quite a while ago. It would be very surprising if they hadn't hammered out some optimization in that time. It's just the nature of things these days, patching isn't a big deal anymore.
It would take a pretty worthless company to charge for fixes to their game. Not even sure if it'd be legal.
Unless the game is totally unplayable without the patch, then there's no issue. You are not legally entitled to performance increases.
Of course, the community backlash would be an absolute hellstorm. And rightfully so.