The whole george zimmerman fiasco is pretty retarded if you ask me. "activists" (Lookup; Violent Malcontents) who don't know the alleged victim personally at all immediately make a bunch of assumptions without any evidence and rail against the court system way before anything even happens, despite there being no decisive evidence, pretty much whatsoever. Yes, let's start convicting people based on emotions, solid reasoning.
And the people who are deadset on him being innocent are just as bad, because as previously mentioned there's no decisive evidence. Unless you know one of the parties involved personally, or are an attorney or some other relevant figure of authority, you really shouldn't be commenting on the validity of the case, or the alleged guilt or innocence in regards to murder. As for selling the gun for a profit, that doesn't prove anything other than resentment, desperation, or tastelessness. Certainly not murder.
However, when the police said that he should have left it alone and gone back home, and he didn't, that's probably cause for charges of some kind, especially considering the consequences, because in that he implicitly admits guilt. Too bad the general public like to blow things they clearly don't understand out of proportion, and ruin things for people who are capable of pathing a charge through more than one braincell in succession.