They have their own yard 3 houses away

Yes that’s their mom and she watched her kids move “do not mow” signs and she just shouted at them. I step outside, spark a joint, wait for her to see me, I quietly go put the signs back up and THEN she moves to her yard…They’re not doing any harm but I mean seriously her backyard is on water and the backyard is like 5 times the size of my yard. Why are people like this? She didn’t even say sorry about them moving the signs or show any intent to go out them back herself.