When we need food?

This morning I was making chocolate-chip pancakes and Micah asked me the question with concern in his voice, "Mom, when we need food, do we stand with a sign by our beds?" Every time we cross the bridge, Micah asks what the signs say that the people are holding. Sometimes we tell him, but other times ("Why lie, I just want beer") we just tell him that they want money. He is very concerned about them and I've thought of getting a bag of McDonald's hamburgers and giving it to the guy with the sign to share with his friends. I'm just not sure how to teach him about that. When he asked why we don't give them money, we said that sometimes they don't make good choices with the money. Something to keep thinking about.