We have a family in our cul de sac with a slew of toddler boys. I've felt a similiar fear of these little monsters. They are allowed to run, ride their bikes, scooters, skateboards, etc all over the street completely without adult supervision ALL DAY LONG!
Whenever I'm outside, they just stop what they are doing and stare at me. Heebie Jeebie factor of 10!
Not to mention, they constantly leave their current modes of transportation (bikes, etc) in the middle of the street or in front of people's driveways. I almost parked on a scooter a couple days ago. One night when it was dark and I was walking the dog, I actually tripped over a skateboard and almost bit the pavement.
We call them "The Darwins" after the Darwin awards, but deep down I believe they are evil beings determined to take over the neighborhood.