Heh. The last couple time I've seen a candidate rejected for "poor culture fit", it was because the candidate themselves demonstrated ageism or racism.
First I was going to express disbelief that any candidate would think that was OK to do. But somebody could be a racist trying to find a racist employer that accepts that kind of talk. Weird & wrong, but rational, and probably something they do all the time in other parts of their life.
Then I had the outlandish idea that the local employment opportunity office is getting especially gung-ho and sending decoys through the pipeline. That would be a fun job. Basically getting paid to be a shock comedian who bombs every time.