Both are obviously used in a teasing-not-quite-nice way to signal that maybe these parents should take a deep breath and assume that they raised their kids well, and that scraping your knee or getting frightened is something that happens in life sooner or later, and the parents' job is to guide and comfort their kids when they do happen.
There was a very high profile case (in DK at least) from 1997 about a mother who left her child outside the restaurant where she was eating (with line-of-sight to the stroller): https://www.theguardian.com/us-news/2017/nov/26/anette-soren...
I might not want to do the same in New York, but in Denmark no one would bat an eye if this happened.