"They" and "Them"

Growing up, my mom taught me to "walk down the middle of the road; that way, they can't get you." I was never really clear who "they" were, but it seemed like really good advice and it stuck with me. John (being John) is quick to point out that while "they" might not be able to get you, cars certainly can. But that doesn't faze me. To this day, I still walk down the middle of the road so they can't get me.