I think frugality is just so effective at providing you more freedom that it becomes a means to any end you can imagine. For some folks it's being a able to raise children, retire early, travel the world, eat healthier, start a business, pursue your hobbies, learn skills, volunteer, and you can go on and on. It's also effective enough that you get to choose not just one of these goals, but several.
For me it probably all started when I was in elementary school and really wanted to get a SNES but it cost a whole $25 (used, N64 was coming out at the time). Thankfully, my parents made me earn and save up enough money before I could get it, although they did help me with generating and executing money making ideas. Ever since I'd been pretty frugal, and was always able to save up anything I desired up until college. Then I discovered climbing and a full time job and it was readily apparent which I would prefer to do for the rest of my life. So then the frugality went into overdrive mode.