Affirmative action is important even to wealthy black families, if the goal is to mirror the mechanical flow of wealth in America's white families.
You can link a source here, as I'm skeptical that this is actually true. That said, many minority students at elite institutions were already attending elite high schools on scholarship - so there is a kernel of truth there.
https://en.wikipedia.org/wiki/Affirmative_Action_Around_the_...
"They tend to benefit primarily the most fortunate among the preferred group (e.g. black millionaires), often to the detriment of the least fortunate among the non-preferred groups (e.g. poor whites)"
If we're just comparing anecdotes, as someone who attended one of these "elite" universities, this didn't seem to be the case at all.