Started casting when I was 19, I remember that because I had to have my Mom buy me a TC 30-30, and I read a lot. I read an article or two about casting, and the idea of making my own bullets seemed cool.
Still doing it in my mid, soon to be late 40's.
You have to understand, and I imagine it is true for a lot of us that cast, but we enjoy making things. I would be a framing carpenter instead of what I do know, except it is fun most of the time and the money is better. I do volunteer with Habitat and Rebuilding Together Houston (Fixing fixed income individuals houses of minor issues). Also build my own bows and furniture.
For me it has always been immensely enjoyable to take raw materials, that are just laying there, shape them, mold them, and manipulate them into something that usable, and contains it's own energy. (bow, ammunition, boolits, etc).