Another post remined me of this..
Last year as I was leaving the grocery store this little boy came barreling past me. He was about two. He was headed full speed for the parking lot which was quite busy. Acting on instinct I grabbed him, picked him up, and carried him back to the parent. She FREAKED on me and told me never to touch her kid again. Ummm... I will do it again if I ever see him running full steam for the parking lot.