I thought stand your ground laws only applied when the shooter didn’t initiate the encounter.

The math on this is just so simple, Zimmerman of his own volition and directly against the 911 operators instruction initiated an unnecessary altercation outside his own “castle,” and ended up shooting and killing an unarmed minor.

If he had his gun out prior to accosting the kid the kid probably reasonably believed that he was being robbed. The only one with the power and ability to prevent the situation from escalating unnecessarily was Zimmerman, who looks like a puffed up vigilante with a history of poor impulse control.