I don't know where you live, but crime of that nature, while not unheard of, is not very common here. Penalties are pretty stiff and people are not afraid to shoot.
One guy here rented a house that had been previously occupied by a drug dealer. The third time he was robbed in his own home, along with his wife, he gave them everything, then followed them outside and killed them both with a shotgun. While not exactly legal, the DA refused to indict. He did not even submit it to the Grand Jury. People don't take kindly to being robbed.
I get it.. You’ll find the keys to mine hanging in the ignition.
I was just pointing out that in the 70’s security was low on the manufacturers list because it was not near the problem it is today.