I think there's a lot of luck involved in being able to do the very first step of that, which is why I really haven't concerned myself with it. It seems to me like the people who seek this are also hyper anxious about their careers and money.

In contrast to what you describe, I find that with the intention to do this sort of thing, you end up predicating your interests based on the price of them entirely, rather than being frugal within them. Camping requires a tent, but if you're not willing to buy one and maybe a backpack and some shoes, you're just dull. I did do this for a period of time, and I look back on it largely with thanks that I didn't continue.

Sometimes this is sensible, sometimes it's not. Getting into car racing or mountaineering is just inherently very very costly, so I'd not blame someone for avoiding them even if they did have the cash. There is just a certain amount of unpleasentness involved in not excessively not spending coupled with excessively working.