I have many rock climbing friends who live on less than 15k a year. They often do it for years, working seasonally 3-5 months a year. the trick is to go somewhere with a very cheap lifestyle. It can be accomplished by living in your car in the mountains, or traveling to SE Asia, etc. The climbing provides something to do and a sense of community.

There are other cultures like this. I’ve seen kids from Europe doing a gap year staying in hostels for very little (they sometimes do some light work for the hostel to get a free place to stay)