Beaten ego?

A few minutes ago a came across a coupel of people. They were sitting outside a restaurant and gossiping. When i walked by i heard one of the womensay: "If he starts crying again, i'm gonna hit him". And one of men started to laugh at this remark. I assume they were talking about a child.

I thought that this was plain sad. Laughing when a child gets hit. And I was wondering why somebody would do something like that.

I have only one explanation. In psychology there is something called downward-comparison. This is when somebody compares himself to someone who is worse at something or in a worse position. It is used to push ones self-esteem by seeing that his situation is not so bad. 

But how broken must ones self-esteem be to get a push out of a beaten child. I think this is an indicator to change something in his life. Something that gives his confidence a better boost.