Popular urban myth. Sounds great and makes sense but there is a caveat: If a burglar knowingly entered an occupied home it means he is prepared to deal with you should you try and crash his party Maybe your burglars are really that smart. I don't mean to argue the point. But honestly, I don't think the burglars in my hometown are all that clever.
BOOM!
It's not so much that they're smart because they're actually dumber than a bag of hammers. If they were bright then they wouldn't be criminals. But our punks are particularly vicious and street wise. They also don't have much fear of death. I see that with my students a lot too. They hear gunshots in the 'hood so much it's a natural event. So many of them have collections of t-shirts that memorialize a dead friend, killed by gang violence or by the cops that they're not really impacted by the thought of dying young and by violence. I think an armed bad guy, inside an unknown home in the dark is going to go postal if he hears the shottie rack because he's going to feel trapped by the layout of the rooms. If he's unaware of a means of exit he's going to become ferocious if he feels threatened. It's a simple fix and I'm not belaboring the point either. Just don't give any warning before you put him in the ground. If there are more than one, I promise you the others will give up meekly after a buddy gets wasted inside a home.