You forgot about the man eating mountain lions, the poison ivy, poison oak, treacherous trails and hills, the ear infections from the water, oh....and don't forget the wild man beast that roams the hillsides. Some of those are pretty scary. <g>
..and lets not forget the environmentalists or the Sierra Club. If it was up to them, only the floods would be allowed to move rocks around in the rivers.
If you do it for a living, it's REALLY, REALLY, hard work.
I dredged for gold for 3 weeks straight, when I was about 20. I came out of the hills in the best physical shape I have ever been in. I felt like a marine, fresh outta boot camp.
I said it was fun. I didn't say it was easy. <g>