Why don't the guests kill each other?

Whether on purpose or by accident, why don’t the guests kill other guests?

I get that the guns don’t hurt the guests, but knifes do and there’s plenty of other ways to kill people.

Hosts look real and guests have trouble telling hosts from other guests so what’s stopping guests from killing each other?

Yes, security is watching, but I doubt they can see everything and even if they could they wouldn’t get into the park fast enough to stop a murder in progress.

The place tends to bring out the worst in people so what’s stopping someone from killing a host and then deciding to kill a guest? Or what’s stopping a guest from killing a host, killing another, killing one more and realizing oops–one of those was actually a guest?

This has bugged me since the first episode so if anyone has any answers, ideas or theories then I’d love to hear them.