Seriously? You don't think it's been established that Trayvon Martin was there as a guest and not a burglar?
The following conditions are not logically inconsistent:
1) Staying in the neighborhood
2) Robbing the neighborhood
Now, I don't think he was one of the burglars who'd been targeting the neighborhood. Because he wasn't from that vicinity... far more likely that his pile of stolen jewelry had come from homes nearer his other residence. Of course, he probably was looking to replace the confiscated pile of jewelry with another pile... so he might well have been casing houses while walking home that night.