Exactly. Search and rescue missions based on the itineraries, last known position reports etc. of missing hikers alone are incredibly resource intensive. It‘s not unlikely for members of the SAR team to get injured or even killed during such an operation.
How do you know if it is a net benefit without knowing the costs?
If the cost of a lost life is infinite, then no operating costs could ever outweigh that.
I've seen a lot of studies that model human life with a dollar amount. It's depressingly low. I think I was reading a traffic study (can't find it) that modeled pedestrian deaths at $1M, in a city where many people walking around have a higher net worth than that (because of housing prices).