but LittleBlueBag, as mentioned above, what if your toddler had dropped the mug on someone foot and it shattered on their leg? What if your other child playing with the car had run into another child, make them trip and broke their legs?
This is what the comment about 'not letting you in public' might have referred to.
In the end, as said, we only had your account of what happened. Maybe that woman was indeed totally over exagerating the situation and letting the frustration of her bad day on you, but at the same time, your first post indicate that your kids are a handful and that you were not supervising them at this point, so it could very well be that they were indeed being a real nuisance or even danger that everyone was obvious to, but you were not.
As said, all you can do is either opt to totally ignore her because she is not worth wasting your energy on if you are totally confident that you kids did nothing wrong and you were not letting them act dangerously, or you can reflect on what she said and consider whether maybe, you were undermining the situation and that maybe, just maybe your kids were acting in a way that very much disturbed others or were potentially causing some hazards.