My view is that a child throwing a tantrum in the supermarket, and a 20-something being bothered by it, are two sides of the same coin. And in fact, I care about the consequences of either behavior, but not the causes.
Of course we care at some level. We're programmed to care, otherwise kids wouldn't have developed the tantrum gene. If my baby has a tantrum in the supermarket, I will swing into tantrum mode and deal with it.
If my kid reaches the age of 20-something, and expresses hostility towards the reasonably expected range of human behaviors observed in a typical civic environment, well, I hope that doesn't happen.
Sure, it takes a village to raise a child. But if it's somebody else's baby, or somebody else's 20-something, then in fact I don't care about it in the same way as if it's my own.