His lack of care came before the actual hike, though. I regularly go hiking in mountains in the winter, and occasionally I'll take someone along with me.

Because this is an activity that can easily lead to disaster for the unprepared, anybody that comes along with me has to be prepared or I'm not letting them come. This means that they have to carry everything they'd need to survive for a few days if we get separated, and that I'm comfortable that they have enough knowledge and skill to survive and find help on their own if needed.

Letting someone come along into a dangerous situation unprepared (let alone intentionally abandoning them) isn't just unempathetic, it's malicious.