Believe me -- they are NOT thinking that they "failed in teaching them how to behave".
They more than likely believe they are "progressive parents", not "stifling" the spirit and individuality of their little darlings by disciplining them and "they're just being kids".
I was at a shop the other day and heard a child wound up into a mad tantrum. Unacceptable IMO, but I'm thinking maybe it's a tired three-year-old who needs to go home. I round the corner and see that it is a girl who is at least six!!!
Losing her mind, stomping around, crying, screaming, sitting on the floor with her arms crossed...I can't even remember what she was babbling about. Her mother was just, "now you have to be quiet. you're in big trouble when you get home (
), etc." It went on for 10 minutes; I had to leave the store.
She's likely the sort of mother who would not be happy if her brat couldn't come to an adult party. She probably can't find anyone to look after the little beast...