Thought this would be about society as a whole
Not one family. They should do another movie but this time have groups of people with plans. Some plan to steal, others to kill specific people and some just out there killing anybody for the fun of it. So, those out there trying to steal also have to avoid being killed, those trying to kill one specific person have to avoid being killed. All in all, it wouldn't be worth it for anyone but serial killers and other psychopaths.
"... and I am unanimous in that!"- Mrs. Slocombe