Hey- don't want to get shot? Don't commit the crime.
I fairly liberal in my leanings, a recovering Republican if you will...but I've got no problem with this personally. These guys made an adult decision. A poorly considered criminal decision, and they paid the price. As a previous 4 year Texas resident, there are certain things I do miss.
While the legal aspects might be a stretch, again, I've got no problems with it. How much of threat does one stand for or accept? A little, some, or do you wait for all of it? If someone is in my house, or on my property and feel afraid or threatened; well someone other than my wife anyway, I'll do what I need to do to. As Jeff Foxworthy so eloquently said, "this a house where a gun lives". If you are hurt or killed during the commission of a crime- nobody owes you anything.
On the other hand, I'm glad to see that there are some non-involved parties who have the strength or wisdom to stand idly by while their next door neighbors are robbed.