I don't know whether this will be popular or not but I have my own theory, I think Zimmerman just didn't have the balls to walk up to this kid and say hi. Are you lost is anything I can do for you? At that point, there would've been no tension and the night would've been uneventful and neither would've given each other a problem. However, having his trusty six shooter packed in his belt. He had the courage to follow this kid which he was told not to do. I really believe this whole thing could've been avoided, that being said, if things went down the way. He said they did and this guy was trying to crack his head open like a nut. Then he had every right to use whatever means he needed to defend himself.