In the first case, there isn't enough of the story to know the exact circumstances.  It's unclear how the situation evolved.  The man supposedly "lunged" for the home owner's gun, yet he was shot in the back?  Was the perp running out of the garage or running inside of the home?  If it was the latter, then it would justify the defense position that the home owner was protecting his family and explain why the thief was shot in the back.

In the second case, it appears that the store owner messed up by not holding the thief at gunpoint until authorities arrived.  Holstering his gun and getting into a fight was the first huge mistake.  The second mistake was shooting him while he was attempting to flee.  A series of very poor decisions were made by the store owner, and though the punishment might seem excessive to some, it was deserved.

In both cases though, both of the thieves got what was coming to them by breaking the law and trying to steal from somebody else.

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