There is more to this story. I wonder if she had them walking on a highway or something. Perhaps she was impeding traffic.
The story has few facts. If the mother is making the kids walk for missing the bus—yet is aware of the “environment” to the point where she is watching them, she is probably not an idiot.
My guess is they were walking on a busy street without sidewalks AND she was impeding traffic. Both of those things are “ticket worthy.”
my guess is that you are on the money. the police don’t like to get involved with family issues unless they feel there is no choice. my guess real young kids under the age of ten. a real dangerous road and a call into 911 by a concerned civilian. this is the type of thing where if IU was a cop responding I would try to give just a warning but if there were multiple calls over the year or the person became angry with the cop and escalated the encounter the cop would of felt he had no choice.