This is Dallas: You Break In, You Get Shot

Apparently people in Dallas take their right to shoot intruders very seriously, like the dry cleaners who shot a would-be thief, and this guy, who has killed two people in the last three weeks. What I don’t get is: Why do these people want to steal from a dry cleaning place and a welding shop? How much money could these mom-and-pop shops possibly have in the stores?
I get that people have the right to defend themselves, their homes, and their businesses, but all this gun toting can be tragic.