I think people make the mistake of thinking that the people who get bonuses are easily replaceable.
The executive market of people who have experience at these kinds of levels is extremely thin. Your company needs to be attractive to this high echelon of talent.
That means keeping a good record of treatment to executives.
I think the thought of: “just pay them less or they can leave” is pretty common. But it’s just not easy to recruit at this level and the responsibility is huge.
There is a slight PR angle to avoid looking greedy, but its moreso just the nature of the talent market at this level.