However, it should be, because it is.
After all, the recidivism rate is staggeringly low for those burglars who have been shot and have spent a peaceful night lying quietly on a tarp to ensure that they have had plenty of time to bleed out and cool down to room temperature. You’re not against cool criminals, are you?
You shoot till you stop the threat then you stop. End of story.
If you have a feeling they need more serious treatment then you need to work on shot placement while in imminent threat of death or serious bodily injury. But once they are down and no longer a threat, you become the criminal if you continue.