Earlier quoted context omitted.
Different people are different I guess. Extra expense and inconvenience also wouldn't bother me. Instead I'd be worried that one day this guy is going to kill everyone while we're sleeping. How well do you really know someone? How well do you really know someone that just showed up at your door days before?
“Overall, 76% of female murders and 56% of male murders were perpetrated by someone known to the victim.” https://bjs.ojp.gov/female-murder-victims-and-victim-offende...
> https://bjs.ojp.gov/female-murder-victims-and-victim-offende...
Lets say M is "being murdered" and A is "stranger in the house", "not A" is "person known to the victim in the house".
The numbers you're quoting say that P(not A | M) is large, implying that P(A | M) is small.
However, to make a decision on whether to let someone in, I care about P(M | A).
You need to exercise that critical thinking more. You just heard someone say "the murders are known to the victim" and you instantly dropped your common sense.