It's their lack of accountability. They all seem to think "if you're not perfect, you can't call me out" but that's as you said very childish. What if everyone makes the same mistake? Are we all gonna stagnate, not learn from the mistake, and wait until some kind of god or angel who doesn't mame it to point it out to us? Unlikely.
But that's what they want: to keep getting away with bad behaviour, whatever it costs, because the alternative brings shame.