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I believe you'll find that generally real-world justice systems handle actions that threaten lives separately from any attendant property crime. We have various forms and levels of "Endangerment" as a separate crime, for example.
I would agree that legal systems tend to categorize crimes in a variety of degrees.
Additionally, I would also posit that legality and morality are not always synonymous.
Legally, I imagine that most contemporary justice systems typically view human life as more important than property.
Historically, that hasn't always been true though. In some places and cultures, the value of a human might be less than the property* of a horse or cow.
(*Ignoring, for the moment, the ethics of categorizing a living creature as property)
Considering contemporary culture, there do exist people for whom defending property (against theft) with violent force would be seen as morally justifiable.
It's not hard to imagine that differences in culture and differences in thought may exist in a fantasy world. Such differences are interesting ways to explore what it means to be a "villain" for PCs.
It's been a while since I have played the Ultima (pc/console) games, but I remember finding out in one of the games that the Avatar character you play as -and is generally seen as the ultimate paragon of good- is seen as the ultimate villain from the perspective of the gargoyles.
Similarly, I recall when WWE wrestler Bret Hart was simultaneously a "heel" in America and a "face" in Canada.
Differences in law, culture, and morality could mean that being a hero or a villain depends upon the longitude and latitude of the PCs.