The OPs question, "Are you inhibited from buying expensive yet affordable gear because of a sense of vulnerability or risk?" implied risk to his personal security, not environmental.
So I add one more rule to live by, to the three I first posted. If you are in an area where you feel at risk, you probably need to move on. A mugger is not going to look at your Nicca III-s and say "Let this one go Rocko, it's not a real Leica!" If a bad person sees a camera, watch, or pair of tennis shoes he's not going to stop because they aren't the top models. Likewise, most random thieves don't know what a good camera is anyway, they just see a target in their domain.
Not that any of this is very likely to happen. But the chances increase when you are in risky areas. People don't get mugged at the Westminster Dog Show. They get mugged late at night, outside of bars, concerts, and places where people drink or are naturally agitated. Or where people are extremely desperate. Yes, those places are photogenic.