I suspect it may be more a reflection of how easily Americans can get FAR from civilisation compared to most Europeans/Brits, and how hostile those places can be compared to our overall pretty mild climate.

Even with the comparatively small distances involved, there are plenty of Brits (and I assume Europeans more generally) who set off for an ill-prepared hike and end up getting saved by mountain rescue because they decided to walk up a mountain in clothing more suited for a walk to the shops.