A question we've all heard before on web boards that doesn't quite have a black and white answer. So a bit of brainstorming below considering the few exceptions.
After decades of backpacking and hiking dozens of dozens of trips, I and none of those I've been with have ever had someone rummage through our gear or take anything. However we also take care of our gear wisely per below. Some of the below is common sense that applies not only in the backcountry but also if one were picnicing at an urban city park.
It is generally safe to leave typical camping gear and items at campsites because the vast majority of backcountry visitors are honest ethical law abiding helpful people. Few urban criminal rip off theft types ever have interests in outdoor mountain activities. But one ought always be aware that yes a few small percent may venture out in our areas.
Backcountry locations more than easy day hiking distance and vertical rise from trailheads are only likely to see other honest ethical law abiding helpful people. And conversely those backcountry locations in easy day hiking range from trailheads are more likely to see visitors unfamiliar with outdoor activities and with urban world behaviors.
The closer a backpacking trailhead is to large urban areas the more likely it is to draw people unfamiliar with outdoor activities and with urban world behaviors.
The large thru hiking trails near entry and exit points are more likely to draw people unfamiliar with outdoor activities and with urban world behaviors.
Trailheads with paved road access are more likely to draw people unfamiliar with outdoor activities and with urban world behaviors, versus those with gravel or dirt road access. And the longer an access road to a trailhead is from highways, the less likely.
One is more likely to have possible gear theft issues along popular busy trails versus trails with low use.
One is far more likely to have possible gear theft issues at campspots within near visual distance of trails than at campspots out of sight of trails.
Rip off types are very unlikely to hike trails with the intent of stealing other visitor's gear. Instead those with such behavioral tendencies are more likely to do so by chance opportunity.
The greater the value of an item the more likely it might be of interest to someone with rip off tendencies. If one placed a wallet with bulging cash out in the open in clear view at a campspot, and it was obvious no one was around, such would be tempting to some individuals that might otherwise never theive. And conversely no one needs to worry about theft of most backpacking gear like a stove, much less a fork and spoon. So the wise thing to do is to not leave expensive small items out at campspots out in the open but rather at least put them away inside a tent or pack.
The easier an item is to remove and conceal, the smaller and lighter, the more likely a rip off minded person might steal something in the backcountry. For instance if one left an expensive DSLR camera out in the open in plain view at a campsite and such a person came by when no one was around, they might be tempted to steal that versus stealing some pricy $400 ultralight tent that would require more time to take down, remove, more effort to carry away, and would be more difficult to conceal along a trail or back at a trailhead.
However if a trailhead was just a mile or so away, yes some poor young urban person with rip off behaviors dayhiking back to a trailhead might be tempted to steal even a whole loaded backpack full of gear, even cheap low quality old gear, sitting along a trail ready to just lift up and carry off if they had watched from a distance, the owner heading off downhill to a nearby lake to go fishing. So don't make theft too tempting.
If one were camped at the always full Little Yosemite Valley camping zone and set off to climb Half Dome, it would not be wise to put a $2000 DSLR camera even inside one's tent while one was away for many hours if many others at the camping zone had watched one use the camera. Same thing with a wallet full of cash and credit cards etc. Much wiser to stash such unseen some distance up a trail where no one would ever have a reason to wander away from a trail edge at.
David Senesac
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