I grew up in a small city in the US and was taught early on to never leave any property in view in your car. The US also has a worse issue than other parts of the world because people often leaves guns in their cars.

Outside of some bad areas of some cities, in New England leaving property in cars is perfectly normal.

Lived in the Bay Area for over two decades. Yeah, leaving a visible item in your car is just bait for the smash-and-grab crowd.

It sucks but once you know it, it would be like thinking you can just leave your wallet sitting on a counter.

Ahem. There are neighborhoods in the US where you leave nothing in your car because otherwise your car will become a target. It's often "the rule" in these places that you also leave the doors unlocked because that way "they" won't break your window trying to get in. They open the door, see there's nothing of value to steal and move on. In other places in the US it's (still but fading) normal to leave your car doors unlocked because "everybody knows everybody and no one would steal from each other." Code switching is knowing which of the neighborhoods you are in and how to adapt.

not "fault" in the sense of legal or ethical blame, but "fault" in the sense of stupid vs. smart thing to do

It 100% is if you live in or operate in a high crime area known for vehicle break-ins. Like OP of the comment.

I imagine they see it the way I do: the SF Bay Area has thieves like this because it's part of local native culture. You get the good with the bad. Sort of like going to the elephant graveyard and being eaten by hyena pack. Sure, it's not your fault for walking around graveyard and getting eaten by hyena. But this is where hyena is. I have lost (and sometimes recovered) many items to these hyena. Ultimately, they are not people or anything. They're like hyena. You don't say it is fault of hyena. It is animal and local culture is animal lover. Why stress about it? Like many, GP decided that he leave hyena here and go elsewhere where it is people and not animal.