system
Given the following post, respond as if you're commenting on Reddit:
human
[Every movie ever] Why would anyone put the keys on the fucking sun visor?

Like, leaving your car either unlocked, or locking your keys in your car so that you can more easily have your car stolen.

Not only that, you’re surely invalidating your insurance for what doesn’t even seem more convenient than keeping your keys in your pocket or in your house.

This is common enough for so many vagabond heroes to use it as their first port of call (including two separate terminators).
gpt
A lot of those vehicles are company or community vehicles - fire trucks, work trucks, etc - and are stored in secured lots and are meant to be shared by multiple drivers. It's sufficiently secure.

Plus, many places exist where cars just don't get stolen. In many rural places, the chances of you forgetting or losing your keys are much higher than of your car getting stolen.