One BEEELLION dollars is proportionate
It would be way too much for your or for me to pay such a sum of money but not for iApple, in this case one billion dollars seems a pretty fair sum, iApple can pay that money very very easily.
iApple routinely pays astronomically high sums of money for no reason so now that there is a fair and very good reason for them to pay why would they balk at it?
Just look at how much much iApple pays tim cook and others, if iApple can so generous with some why would they behave like a scrooge with Bah?