American blacks are certainly conditioned to celebrate when another black does well in life, so that would be part of it.
And we are conditioned to treating our Presidents as royalty. The Last President who lived frugally was Calvin Coolidge. Harry Truman lived something like a middle class life style. Jimmy Carter made a show of it, but Reagan brought back the imperial style, which Obama is now doing with “Flash.”
you wrote:
“American blacks are certainly conditioned to celebrate when another black does well in life, so that would be part of it.”
I think many blacks are conditioned to celebrate when another black pulls one over on whitey, cons the system, beats the man, etc. You DO NOT see blacks celebrating the success of blacks who have worked hard, studied hard, planned, saved, built, joined the military to get out of the ghetto, raised their own kids, took responsibility, etc.