Wow. I've had no problems like this. I have a couple young kids who live behind me. They asked if they could pick the raspberries. Sure, I'm not going to eat them all. Turns out they were too well mannered to pick the ones that had grown on the other side of the chain link with out asking first!
I also had one boy at the end of my street who wanted a flower for his mother. He diligently went to pick one of my tulips. Pulled the entire bulb out of the ground. I just laughed it off because it was too funny to watch. He was maybe 5 or 6. Now, had this been one of my adult neighbors, we would have had words...